View Filing Data

70.4

69.1

67.9

General and administrative

(14.6)

(13.0)

(11.0)

(8.7)

(4.4)

(6.2)

Financial charges and other (Note 8)

(15.2)

(15.0)

(14.7)

(28.0)

(25.6)

(29.3)

Net income allocated to partners

157.4

^[1],[2]

137.1

^[2]

106.1

^[2],[3]

Net income allocation (Note 9)

Common units

154.3

134.4

90.6

General partner

3.1

2.7

7.2

$ 157.4

$ 137.1

$ 97.8

Net income per common unit (Note 9) (in dollars per unit) | $ / shares

3.02

2.91

2.34

Weighted average common units outstanding (millions) (in units) | shares

51.1

46.2

38.7

Common units outstanding, end of year (millions) (in units) | shares

53.5

46.2

[1]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[2]	Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[3]	Recast as discussed in Notes 2 and 5.

CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2009

Change associated with current period hedging transactions (Note 14)

^[2]

$ 157.4

^[1]

$ 137.1

$ 106.1

^[3]

Other comprehensive income

13.8

10.0

7.9

Change associated with current period hedging transactions of investees

0.1

0.5

1.3

Total other comprehensive income

13.9

10.5

9.2

Total comprehensive income

$ 171.3

$ 147.6

$ 115.3

[1]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[2]	Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[3]	Recast as discussed in Notes 2 and 5.

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 8, 9, 10, 11, 12, 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 30
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A5
-Appendix A

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e557-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e540-108580

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6508144

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 10, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28, 29, 30
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 19

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 20
-Article 9

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.18)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.19)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e565-108580

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.22)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph d
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-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A7
-Appendix A

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period attributable to the parent entity. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 30
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 29
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=6921628&loc=SL4569643-111683

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=6921628&loc=SL4569616-111683

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6921930&loc=SL4573702-111684

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

CONSOLIDATED STATEMENT OF CASH FLOWS - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2009

Cash Generated From Operations

^[2]

$ 157.4

^[1]

$ 137.1

$ 106.1

^[3]

Amortization of debt issue costs (Note 8)

15.2

15.0

14.7

2.0

0.5

0.4

(Decrease)/increase in other long-term liabilities

(0.9)

0.6

0.3

Equity allowance for funds used during construction

(0.3)

(0.5)

(Increase)/decrease in operating working capital (Note 11)

(3.0)

3.1

2.5

Total cash generated from operations

169.2

156.0

123.5

Increase in investing working capital (Note 11)

Capital expenditures

(3.5)

(9.3)

(1.9)

(2.9)

Total investing activities

(547.8)

10.6

(269.8)

Financing Activities

Distributions paid (Note 10)

(154.8)

(138.7)

(117.0)

Equity issuances, net

337.6

265.6

Long-term debt issued (Note 6)

894.4

74.0

208.0

Long-term debt repaid (Note 6)

(665.8)

(101.4)

(203.5)

Debt issue costs

(6.9)

Total financing activities

404.5

(166.1)

141.0

Increase/(decrease) in cash and cash equivalents

25.9

0.5

(5.3)

Cash and cash equivalents, beginning of year

3.6

3.1

8.4

Cash and cash equivalents, end of year

29.5

3.6

3.1

Interest payments made

13.1

8.5

16.5

GTN and Bison

Acquisition

(538.7)

GTN

Cumulative distributions in excess of equity earnings:

^[1]

21.1

Bison

Cash Generated From Operations

Equity earnings in excess of cumulative distributions:

^[1]

(1.5)

Great Lakes

Cumulative distributions in excess of equity earnings:

13.4

10.5

13.4

Investment

(8.9)

(9.3)

(0.1)

Northern Border

Cumulative distributions in excess of equity earnings:

23.6

$ 18.7

35.4

Investment

$ (54.8)

(42.3)

North Baja Pipeline, LLC

Due to North Baja's former parent (Note 6)

Acquisition

(271.4)

Financing Activities

$ (12.1)

[1]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[2]	Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[3]	Recast as discussed in Notes 2 and 5.

CONSOLIDATED STATEMENT OF CHANGES IN PARTNERS' EQUITY - USD ($)
shares in Millions, $ in Millions

Total

Common Units

General Partner

Accumulated Other Comprehensive Loss

Partners' equity at Dec. 31, 2008

$ 875.6

$ 891.4

$ 19.1

$ (34.9)

Partners' equity (in units) at Dec. 31, 2008

34.9

Increase (Decrease) in Partners' Equity

Net income attributed to former North Baja owner

^[2]

$ 106.1

^[1]

$ 98.8

7.3

(8.3)

(8.2)

(0.1)

Equity issuances, net (Notes 5 and 7)

$ 265.6

$ 260.2

5.4

Equity issuances, net (Notes 5 and 7) (in units)

11.3

Distributions paid

$ (117.0)

$ (109.4)

(7.6)

Excess purchase price over net acquired assets (Note 5)

(27.7)

(27.2)

(0.5)

Other comprehensive income

9.2

Partners' equity at Dec. 31, 2009

$ 1,103.5

$ 1,105.6

23.6

(25.7)

Partners' equity (in units) at Dec. 31, 2009

46.2

Increase (Decrease) in Partners' Equity

Excess purchase price over net acquired assets (Note 5)

^[1]

$ 137.1

$ 134.4

2.7

Distributions paid

(138.7)

(135.9)

(2.8)

0.1

Other comprehensive income

10.5

Partners' equity at Dec. 31, 2010

$ 1,112.5

$ 1,104.2

23.5

(15.2)

Partners' equity (in units) at Dec. 31, 2010

46.2

Increase (Decrease) in Partners' Equity

Equity issuances, net (Notes 5 and 7)

^[3]

$ 157.4

^[1]

$ 154.3

3.1

$ 337.6

$ 330.9

6.7

Equity issuances, net (Notes 5 and 7) (in units)

7.3

Distributions paid

$ (154.8)

$ (151.7)

(3.1)

Excess purchase price over net acquired assets (Note 5)

(133.6)

(130.9)

(2.7)

Other comprehensive income

13.9

Partners' equity at Dec. 31, 2011

$ 1,333.0

$ 1,306.8

$ 27.5

$ (1.3)

Partners' equity (in units) at Dec. 31, 2011

53.5

[1]	Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[2]	Recast as discussed in Notes 2 and 5.
[3]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.

ORGANIZATION

12 Months Ended

Dec. 31, 2011

ORGANIZATION

ORGANIZATION

NOTE 1 ORGANIZATION

TC PipeLines, LP and its subsidiaries are collectively referred to herein as the Partnership. The Partnership was formed by TransCanada PipeLines Limited, a wholly-owned subsidiary of TransCanada Corporation (TransCanada Corporation together with its subsidiaries collectively referred to herein as TransCanada), to acquire, own and participate in the management of energy infrastructure assets in North America.

The Partnership owns the following interests in natural gas pipeline systems:

•: a 46.45 percent general partner interest in Great Lakes Gas Transmission Limited Partnership (Great Lakes), a Delaware limited partnership. Great Lakes owns a 2,115-mile pipeline that transports natural gas serving markets in Minnesota, Wisconsin, Michigan and Eastern Canada;
•: a 50 percent general partner interest in Northern Border Pipeline Company (Northern Border), a Texas general partnership. Northern Border owns a 1,407-mile U.S. interstate pipeline system that transports natural gas from the Montana-Saskatchewan border to markets in the Midwestern U.S.;
•: a 25 percent interest in Gas Transmission Northwest LLC (GTN), a Delaware limited liability company. GTN owns a 1,353-mile pipeline that transports natural gas from the British Columbia, Canada/Idaho border to a point at the Oregon/California border;
•: a 25 percent interest in Bison Pipeline LLC (Bison), a Delaware limited liability company. Bison owns a 303-mile pipeline that transports natural gas from the Powder River Basin in Wyoming to Northern Border's pipeline system in North Dakota;
•: a 100 percent interest in North Baja Pipeline, LLC (North Baja), a Delaware limited liability company. North Baja owns an 86-mile U.S. interstate pipeline system that transports natural gas between an interconnection with El Paso Natural Gas Company (EPNG) pipeline near Ehrenberg, Arizona and an interconnection near Ogilby, California on the California/Mexico border with the Gasoducto Rosarito natural gas pipeline system; and
•: a 100 percent interest in Tuscarora Gas Transmission Company (Tuscarora), a Nevada general partnership. Tuscarora owns a 305-mile U.S. interstate pipeline system that transports natural gas from Oregon, where it interconnects with facilities of GTN, to a terminus in Northern Nevada.

The Partnership is managed by its General Partner, TC PipeLines GP, Inc. (General Partner), an indirect wholly-owned subsidiary of TransCanada. The General Partner provides management and operating services for the Partnership and is reimbursed for its costs and expenses. In addition to its aggregate two percent general partner interest in the Partnership, the General Partner owns 5,797,106 common units, together with its general partner interest, representing an effective 12.6 percent interest in the Partnership at December 31, 2011. TransCanada also indirectly holds an additional 11,287,725 common units representing a 20.7 percent limited partner interest in the Partnership for a total interest in the Partnership of 33.3 percent at December 31, 2011.

SIGNIFICANT ACCOUNTING POLICIES

12 Months Ended

Dec. 31, 2011

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES

NOTE 2 SIGNIFICANT ACCOUNTING POLICIES

(a) Basis of Presentation

The accompanying financial statements and related notes present the financial position of the Partnership as of December 31, 2011 and 2010 and the results of its operations, cash flows and changes in partners' equity for the years ended December 31, 2011, 2010 and 2009. The Partnership uses the equity method of accounting for its investments in Great Lakes, Northern Border, GTN and Bison, over which it is able to exercise significant influence. The Partnership consolidates its investments in North Baja and Tuscarora.

Amounts are stated in U.S. dollars.

(b) Acquisitions

On May 3, 2011, the Partnership acquired a 25 percent membership interest in each of GTN and Bison from subsidiaries of TransCanada (Acquisitions). The Acquisitions were accounted for as transactions between entities under common control, whereby the equity investments in GTN and Bison were recorded at TransCanada's carrying values. See Note 5 for additional disclosure regarding the Acquisitions.

On July 1, 2009, the Partnership acquired a 100 percent interest in North Baja from a subsidiary of TransCanada. The acquisition was accounted for as a transaction between entities under common control whereby the assets and liabilities of North Baja were recorded at TransCanada's carrying value and the Partnership's historical financial information was recast to include North Baja for all periods presented on a consolidated basis. Refer to Note 5 for additional disclosure regarding the North Baja acquisition.

(c) Use of Estimates

The preparation of financial statements in conformity with United States of America (U.S.) generally accepted accounting principles (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Although management believes these estimates are reasonable, actual results could differ from these estimates. In the opinion of management, these consolidated financial statements have been properly prepared within reasonable limits of materiality and include all adjustments (consisting of normal recurring accruals) necessary for a fair presentation of the financial results for the periods presented.

(d) Cash and Cash Equivalents

The Partnership's short-term investments with original maturities of three months or less are considered to be cash equivalents and are recorded at cost, which approximates market value.

(e) Plant, Property and Equipment

Plant, property and equipment of North Baja and Tuscarora are stated at original cost. Costs of restoring the land above and around the pipeline are capitalized to pipeline facilities and depreciated over the remaining life of the related pipeline facilities. Depreciation of pipeline facilities and compression equipment is provided on a straight-line composite basis over the estimated useful life of the pipeline and compression equipment of 20 to 30 years. Metering and other is depreciated on a straight-line basis over the estimated useful lives of the equipment, which range from 5 to 30 years. Repair and maintenance costs are expensed as incurred. Costs that are considered a betterment are capitalized. An allowance for funds used during construction, using the rate of return on rate base approved by the Federal Energy Regulatory Commission (FERC), is capitalized and included in the cost of plant, property and equipment. Amounts included in construction work in progress are not amortized until transferred into service.

(f) Long-lived Assets

Long-lived assets, such as property, plant, and equipment, and purchased intangible assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group be tested for possible impairment, we first compare undiscounted cash flows expected to be generated by that asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying value exceeds its fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary.

(g) Partners' Equity

Costs incurred in connection with the issuance of units are deducted from the proceeds received.

(h) Revenue Recognition

Transmission revenues relate to North Baja and Tuscarora operations and are recognized in the period in which the service is provided. When a rate case is pending final FERC approval, a portion of the revenue collected is subject to possible refund. As of December 31, 2011, 2010 and 2009, the Partnership has not recognized any transmission revenue that is subject to possible refund.

(i) Income Taxes

The Partnership is not subject to federal or state income tax. The tax effect of the Partnership's activities accrues to its partners. The Partnership's taxable income or loss, which may vary substantially from the net income or loss reported in the consolidated statement of income, is includable in the federal income tax returns of each partner. The aggregate difference in the basis of the Partnership's net assets for financial and income tax purposes cannot be readily determined because all information regarding each partner's tax attributes related to the partnership is not available.

(j) Acquisitions and Goodwill

The Partnership accounts for business acquisitions from third parties using the purchase method of accounting and, accordingly, the assets and liabilities of the acquired entities are recorded at their estimated fair values at the date of acquisition. The excess of the purchase price over the fair value of net assets acquired is attributed to goodwill. Goodwill is not amortized for accounting purposes; however, it is tested on an annual basis for impairment, or more frequently if any indicators of impairment are evident.

The Partnership accounts for business acquisitions between entities under common control using a method, whereby the assets and liabilities of the acquired entities are recorded at TransCanada's carrying value and the Partnership's historical financial information is recast to include the acquired entities for all periods presented. If the fair market value paid for the acquired entities is greater than the recorded net assets of the acquired entities, the excess purchase price paid is recorded as a reduction to Partners' Equity. Similarly, if the fair market value paid for the acquired entities is less than the recorded net assets of the acquired entities, the excess of assets acquired is recorded as an increase to Partners' Equity.

(k) Derivative Financial Instruments and Hedging Activities

The Partnership recognizes all derivative instruments as either assets or liabilities in the balance sheet at their respective fair values. For derivatives designated in hedging relationships, changes in the fair value are either offset through earnings against the change in fair value of the hedged item attributable to the risk being hedged or recognized in accumulated other comprehensive income, to the extent the derivative is effective at offsetting the changes in cash flows being hedged until the hedged item affects earnings.

The Partnership only enters into derivative contracts that it intends to designate as a hedge of a forecasted transaction or the variability of cash flows to be received or paid related to a recognized asset or liability (cash flow hedge). For all hedging relationships, the Partnership formally documents the hedging relationship and its risk management objective and strategy for undertaking the hedge, the hedging instrument, the hedged transaction, the nature of the risk being hedged, how the hedging instrument's effectiveness in offsetting the hedged risk will be assessed prospectively and retrospectively, and a description of the method used to measure ineffectiveness. The Partnership also formally assesses, both at the inception of the hedging relationship and on an ongoing basis, whether the derivatives that are used in hedging relationships are highly effective in offsetting changes in cash flows of hedged transactions. For derivative instruments that are designated and qualify as part of a cash flow hedging relationship, the effective portion of the gain or loss on the derivative is reported as a component of other comprehensive income and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. Gains and losses on the derivative representing either hedge ineffectiveness or hedge components excluded from the assessment of effectiveness are recognized in current earnings.

The Partnership discontinues hedge accounting prospectively when it determines that the derivative is no longer effective in offsetting cash flows attributable to the hedged risk, the derivative expires or is sold, terminated, or exercised, the cash flow hedge is de-designated because a forecasted transaction is not probable of occurring, or management determines to remove the designation of the cash flow hedge.

In all situations in which hedge accounting is discontinued and the derivative remains outstanding, the Partnership continues to carry the derivative at its fair value on the balance sheet and recognizes any subsequent changes in its fair value in earnings. When it is probable that a forecasted transaction will not occur, the Partnership discontinues hedge accounting and recognizes immediately in earnings gains and losses that were accumulated in other comprehensive income related to the hedging relationship.

(l) Asset Retirement Obligation

The Partnership recognizes and measures liabilities associated with the retirement of tangible long-lived assets at fair value as incurred and capitalizes them as part of the cost of the related tangible long-lived assets. Accretion of the liabilities due to the passage of time is classified as an operating expense. Retirement obligations associated with relevant long-lived assets are those for which a legal obligation exists under enacted laws, statutes, ordinances, or written or oral contracts, including obligations arising under the doctrine of promissory estoppel.

The fair value of a liability for an asset retirement obligation is recorded during the period in which the liability is incurred, if a reasonable estimate of fair value can be made. Asset retirement obligations exist for certain of our transmission assets; however, the fair value of the obligations cannot be determined due to the inability to determine the scope of asset retirements, as well as the end of the transmission system life is not determinable with the degree of accuracy necessary to currently establish a liability for the obligation.

We are required to operate and maintain our natural gas pipeline systems, and intend to do so as long as supply and demand for natural gas exists, which we expect for the foreseeable future. Therefore, we believe our natural gas pipeline system assets have indeterminate lives and, accordingly, have recorded no asset retirement liabilities as of December 31, 2011 and 2010. We continue to evaluate our asset retirement obligations and future developments that could impact amounts in our records.

(m) Government Regulation

North Baja and Tuscarora, the Partnership's wholly-owned pipeline systems, are subject to regulation by the FERC. Under regulatory accounting principles, certain assets or liabilities that result from the regulated ratemaking process may be recorded that would not be recorded under GAAP for non-regulated entities. The Partnership regularly evaluates the continued applicability of regulatory accounting, considering such factors as regulatory changes, the impact of competition, and the ability to recover regulatory assets. As of December 31, 2011, Tuscarora has no regulatory assets (2010 – nil) and $0.2 million in regulatory liabilities (2010 – $0.5 million). North Baja has no regulatory assets or liabilities as of December 31, 2011 and 2010. Allowance for funds used during construction is capitalized and included in plant, property and equipment.

(n) Debt Issuance Costs

Costs related to the issuance of debt are deferred and amortized using the effective interest rate method over the term of the related debt.

INVESTMENTS IN UNCONSOLIDATED AFFILIATES

12 Months Ended

Dec. 31, 2011

INVESTMENTS IN UNCONSOLIDATED AFFILIATES

INVESTMENTS IN UNCONSOLIDATED AFFILIATES

NOTE 3 INVESTMENTS IN UNCONSOLIDATED AFFILIATES

Great Lakes, Northern Border, GTN and Bison are regulated by the FERC and are operated by TransCanada. We use the equity method of accounting for our interests in our equity investees.

		Equity Earnings from Unconsolidated Affiliates			Investment in Unconsolidated Affiliates

		Year Ended December 31			December 31
	Ownership Interest at December 31, 2011	Year Ended December 31			December 31
(unaudited) (millions of dollars)	Ownership Interest at December 31, 2011	2011	2010	2009	2011	2010

Great Lakes	46.45%	59.5	58.7	59.1	685.5	690.0
Northern Border^(a)	50%	75.5	67.3	40.3	536.1	504.8
GTN^(b)	25%	11.5	–	–	225.1	–
Bison^(b)	25%	7.0	–	–	162.8	–

		153.5	126.0	99.4	1,609.5	1,194.8

(a): Equity income from Northern Border is net of the 12-year amortization of a $10 million transaction fee paid to the operator of Northern Border at the time of the Partnership's additional 20 percent acquisition in April 2006.
(b): Represents equity earnings from May 3, 2011, date of acquisition, to December 31, 2011.

Great Lakes

The Partnership owns a 46.45 percent general partner interest in Great Lakes. TransCanada owns the other 53.55 percent partnership interest. TC GL Intermediate Limited Partnership, as one of the general partners, may be exposed to the commitments and contingencies of Great Lakes. The Partnership holds a 98.9899 percent limited partnership interest in TC GL Intermediate Limited Partnership.

Rates on the Great Lakes Pipeline are based on a July 2010 FERC approved settlement which became effective May 1, 2010 and applies to all current and future shippers on Great Lakes.

The Partnership recorded no undistributed earnings from Great Lakes for the years ended December 31, 2011, 2010, and 2009.

At December 31, 2011 the partnership had a $458.4 million (2010 – $458.4 million) difference between the carrying value of Great Lakes and the underlying equity in the net assets primarily resulting from the recognition and inclusion of goodwill in the Partnership's investment in Great Lakes relating to the Partnership's February 2007 acquisition of a 46.45 percent general partner interest in Great Lakes.

The Partnership made equity contributions to Great Lakes of $4.2 million and $4.6 million in the first quarter and fourth quarter of 2011, respectively. These amounts represent the Partnership's 46.45 percent share of a $9.0 million and $10.0 million cash call from Great Lakes to make scheduled debt repayments.

The summarized financial information for Great Lakes is as follows:

December 31 (millions of dollars)	2011	2010


Assets
Current assets	65.3	83.7
Plant, property and equipment, net	826.2	846.9
Other assets	0.6	0.6

	892.1	931.2

Liabilities and Partners' Equity
Current liabilities	30.0	34.9
Deferred credits	0.4	5.6
Long-term debt, including current maturities	373.0	392.0
Partners' capital	488.7	498.7

	892.1	931.2

Year ended December 31 (millions of dollars)	2011		2010		2009


Transmission revenues	250.0		262.4		289.7
Operating expenses	(61.8	)	(59.2	)	(66.5	)
Depreciation	(32.2	)	(40.5	)	(58.5	)
Financial charges and other	(29.9	)	(30.9	)	(31.9	)
Michigan business tax	1.9		(5.3	)	(5.4	)

Net income	128.0		126.5		127.4

Northern Border

The Partnership owns a 50 percent general partner interest in Northern Border. The other 50 percent partnership interest in Northern Border is held by ONEOK Partners, L.P., a publicly traded limited partnership.

TC PipeLines Intermediate Limited Partnership, as one of the general partners, may be exposed to the commitments and contingencies of Northern Border. The Partnership holds a 98.9899 percent limited partnership interest in TC PipeLines Intermediate Limited Partnership.

The Partnership recorded no undistributed earnings from Northern Border for the years ended December 31, 2011, 2010 and 2009.

At December 31, 2011, the Partnership had a $119.9 million (2010 – $120.8 million) difference between the carrying value of Northern Border and the underlying equity in the net assets primarily resulting from the recognition and inclusion of goodwill in the Partnership's investment in Northern Border relating to the Partnership's April 2006 acquisition of an additional 20 percent general partnership interest in Northern Border.

Northern Border's distribution policy adopted in 2006 defines minimum equity to total capitalization to be used by its Management Committee to establish the timing and amount of required equity contributions. In accordance with this policy, the Partnership made the required equity contributions of $49.8 million in the third quarter of 2011 and $5 million in the fourth quarter of 2011 to meet minimum equity to total capitalization requirements and to fund capital expenditures related to the Princeton Lateral Project respectively.

The summarized financial information for Northern Border is as follows:

December 31 (millions of dollars)		2011		2010


Assets
Cash and cash equivalents		32.8		10.2
Other current assets		35.6		37.1
Plant, property and equipment, net		1,266.6		1,294.8
Other assets		31.4		22.9

		1,366.4		1,365.0

Liabilities and Partners' Equity
Current liabilities		48.6		46.7
Deferred credits and other		12.8		9.7
Long-term debt, including current maturities		472.6		540.6
Partners' equity
	Partners' capital	835.1		770.9
	Accumulated other comprehensive loss	(2.7	)	(2.9	)

		1,366.4		1,365.0

Year ended December 31 (millions of dollars)	2011		2010		2009


Transmission revenues	310.1		295.1		249.2
Operating expenses	(73.2	)	(74.0	)	(70.8	)
Depreciation	(61.6	)	(61.5	)	(61.9	)
Financial charges and other	(22.6	)	(23.4	)	(34.4	)

Net income	152.7		136.2		82.1

GTN

On May 3, 2011, the Partnership acquired a 25 percent membership interest in GTN from a subsidiary of TransCanada. The acquisition was accounted for as a transaction between entities under common control, whereby the equity investment in GTN was recorded at TransCanada's carrying value. See Note 5 for additional disclosure regarding the Acquisitions.

TC PipeLines Intermediate Limited Partnership, as one of the general partners, may be exposed to the commitments and contingencies of GTN. The Partnership holds a 98.9899 percent limited partnership interest in TC PipeLines Intermediate Limited Partnership.

On August 12, 2011, GTN filed a petition with the FERC requesting approval of a Stipulation and Agreement of Settlement (GTN Settlement) with shippers and regulators regarding GTN's rates and terms and conditions of service. In November 2011, the FERC approved the GTN Settlement without modification, effective January 1, 2012. The GTN Settlement includes a moratorium on the filing of future rate proceedings until December 31, 2015. Following the expiration of the moratorium, GTN must file a rate case such that the new rates will be effective January 1, 2016. GTN's new rates were determined in a settlement reflecting GTN's rate base, revenue requirement and contract levels.

The Partnership recorded no undistributed earnings from GTN for the year ended December 31, 2011.

The summarized financial information for GTN from May 3, 2011, date of acquisition, to December 31, 2011 is as follows:

December 31 (millions of dollars)		2011


Assets
Current assets		54.6
Plant, property and equipment, net		1,207.2
Other assets		1.1

		1,262.9

Liabilities and Members' Equity
Current liabilities		17.7
Deferred credits and other		19.7
Long-term debt, including current maturities		325.0
Members' capital		900.5

		1,262.9

For the period May 3 to December 31, 2011 (millions of dollars)


Transmission revenues	133.2
Operating expenses	(36.7	)
Depreciation	(36.2	)
Financial charges and other	(15.0	)

Net income	45.3

Bison

On May 3, 2011, the Partnership acquired a 25 percent membership interest in Bison from a subsidiary of TransCanada. The acquisition was accounted for as a transaction between entities under common control, whereby the equity investment in Bison was recorded at TransCanada's carrying value. See Note 5 for additional disclosure regarding the Acquisitions.

TC PipeLines Intermediate Limited Partnership, as one of the general partners, may be exposed to the commitments and contingencies of Bison. The Partnership holds a 98.9899 percent limited partnership interest in TC PipeLines Intermediate Limited Partnership.

The Partnership recorded undistributed earnings from Bison of $1.5 million, from May 3, 2011, date of acquisition, to December 31, 2011.

The summarized financial information for Bison from May 3, 2011, date of acquisition, to December 31, 2011, is as follows:

December 31 (millions of dollars)		2011


Assets
Current assets		9.9
Plant, property and equipment, net		657.9
Other assets		–

		667.8

Liabilities and Members' Equity
Current liabilities		16.8
Members' capital		651.0

		667.8

For the period May 3 to December 31, 2011 (millions of dollars)


Transmission revenues	51.8
Operating expenses	(11.3	)
Depreciation	(12.4	)

Net income	28.1

The entire disclosure for equity investment, or group of investments, for which combined disclosure is appropriate, including: (a) the name of each investee and percentage of ownership of common stock, (b) accounting policies for investments in common stock, (c) difference between the amount at which the investment is carried and the amount of underlying equity in net assets and the accounting treatment of the difference, (d) the total fair value of each identified investment for which a market value is available, (e) summarized information as to assets, liabilities, and results of operations of the investees (for investments in unconsolidated subsidiaries, common stock of joint ventures, or other investments using the equity method), and (f) material effects of possible conversions, exercises, or contingent issuances of the investee. Other disclosures include (a) the names of any investee in which the investor owns 20 percent or more of the voting stock and investment is not accounted for using the equity method, and the reasons why not, and (b) the names of any investee in which the investor owns less than 20 percent of the voting stock and the investment is accounted for using the equity method, and the reasons why it is.

PLANT, PROPERTY AND EQUIPMENT

PLANT, PROPERTY AND EQUIPMENT

12 Months Ended

Dec. 31, 2011

PLANT, PROPERTY AND EQUIPMENT

NOTE 4 PLANT, PROPERTY AND EQUIPMENT

The following table includes plant, property and equipment from North Baja and Tuscarora.

	2011			2010

December 31 (millions of dollars)	Cost	Accumulated Depreciation	Net Book Value	Cost	Accumulated Depreciation	Net Book Value

Pipeline	290.0	110.0	180.0	290.1	100.6	189.5
Compression	104.8	19.5	85.3	113.4	24.5	88.9
Metering and other	42.4	9.3	33.1	42.2	8.2	34.0
Under construction	0.1	–	0.1	0.2	–	0.2

	437.3	138.8	298.5	445.9	133.3	312.6

The entire disclosure for long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software. This disclosure may include property plant and equipment accounting policies and methodology, a schedule of property, plant and equipment gross, additions, deletions, transfers and other changes, depreciation, depletion and amortization expense, net, accumulated depreciation, depletion and amortization expense and useful lives, income statement disclosures, assets held for sale and public utility disclosures.

ACQUISITIONS AND REVISED INCENTIVE DISTRIBUTION RIGHTS

ACQUISITIONS AND REVISED INCENTIVE DISTRIBUTION RIGHTS

12 Months Ended

Dec. 31, 2011

ACQUISITIONS AND REVISED INCENTIVE DISTRIBUTION RIGHTS

NOTE 5 ACQUISITIONS AND REVISED INCENTIVE DISTRIBUTION RIGHTS

GTN and Bison Equity Investment Acquisitions

On May 3, 2011, the Partnership acquired 25 percent membership interests in GTN and Bison from subsidiaries of TransCanada.

The GTN pipeline system extends from an interconnection near Kingsgate, British Columbia, Canada at the Canadian border to a point near Malin, Oregon at the California border. The Bison pipeline system extends from the Powder River Basin near Gillette, Wyoming to Northern Border's pipeline system in Morton County, North Dakota. GTN and Bison are both Delaware limited liability companies regulated by the FERC, and they are operated by subsidiaries of TransCanada.

The total purchase price of the Acquisitions was $605.0 million (the Purchase Price). The Purchase Price consisted of (i) $405.0 million for the GTN membership interest (less $81.3 million, which reflected 25 percent of GTN's outstanding debt at the time of the acquisition), (ii) $200.0 million for the membership interest in Bison (less a $9.1 million future capital commitment to complete the Bison pipeline) (iii) $23.5 million at closing and (iv) $0.6M in working capital adjustments paid in the fourth quarter of 2011. The resulting $538.7 million paid by the Partnership was financed through a combination of (i) an issuance of 7,245,000 common units offered to the public at $47.58 per common unit resulting in net proceeds of $330.9 million, (ii) a draw of $61.0 million on the Partnership's committed $400.0 million bridge loan facility, (iii) a draw of $125.0 million on the Partnership's then existing $250.0 million senior revolving credit facility, (iv) a capital contribution from the General Partner of $6.7 million, which was required to maintain the General Partner's effective two percent general partner interest in the Partnership, and (v) approximately $15.1 million of cash on hand.

The Acquisitions were accounted for as transactions between entities under common control, whereby the equity investments in both GTN and Bison were recorded at TransCanada's carrying values of $246.2 million and $161.3 million, respectively. As the fair market value paid for the membership interests in GTN and Bison was greater than the recorded equity investments in GTN and Bison, the total excess purchase price paid of $131.2 million was recorded as a reduction to Partners' Equity.

Yuma Lateral Asset Acquisition

At the time of the July 1, 2009 acquisition of North Baja, TransCanada had begun an expansion project of the North Baja pipeline from the Mexico/Arizona border to Yuma, Arizona (Yuma Lateral). The Partnership agreed to acquire the expansion facilities and contracts for an additional sum up to $10.0 million, if TransCanada completed the project by June 30, 2010. On March 5, 2010, the Partnership acquired the expansion facilities and contracts in place at that time for a purchase price of $7.6 million. The Yuma Lateral was placed into service on March 13, 2010. The North Baja Acquisition Agreement provided that an additional payment of up to $2.4 million be made to TransCanada in the event that any other shippers contracted for services on the Yuma Lateral before June 30, 2010. A potential shipper signed a precedent agreement with North Baja on June 29, 2010 to enter into agreements for service on the Yuma Lateral. Accordingly, an amendment to the Acquisition Agreement between the Partnership and TransCanada was entered into on June 29, 2010 to allow TransCanada to continue to pursue additional contracts until December 31, 2010. On July 28, 2010, TransCanada secured additional contracts and, as a result, the Partnership paid $2.4 million to TransCanada on March 25, 2011 when the facilities associated with the additional contracts were completed.

The Yuma Lateral asset purchase was accounted for as a transaction between entities under common control whereby the assets acquired were recorded at TransCanada's carrying value. As the fair value paid for the Yuma Lateral assets of $10.0 million was greater than the $7.7 million recorded as plant, property and equipment, the excess of $2.3 million was recorded as a decrease to Partners' Equity at December 31, 2011.

North Baja Acquisition

On July 1, 2009, the Partnership acquired a 100 percent interest in North Baja, a Delaware limited liability company, from TransCanada. The North Baja pipeline system extends from an interconnection with EPNG near Ehrenberg, Arizona to a point near Ogilby, California on the California/Mexico border where it connects with the Gasoducto Rosarito natural gas pipeline system owned by Sempra Energy International. North Baja is regulated by the FERC and is operated by TransCanada.

The purchase price of $271.4 million was financed through a combination of (i) a draw of $170.0 million on the Partnership's then existing $250.0 million senior revolving credit facility (ii) issuance of 2,609,680 common units at $30.042 per common unit to TransCanada for net proceeds of $78.4 million, (iii) issuance of additional general partner interest to the General Partner of $1.6 million, which was required to maintain the General Partner's effective two percent general partner interest in the Partnership, and (iv) approximately $21.4 million of cash on hand.

The acquisition of North Baja was accounted for as a transaction between entities under common control whereby the assets and liabilities of North Baja were recorded at TransCanada's carrying value and the Partnership's historical financial information was recast to include North Baja for all periods presented. The purchase price was allocated as follows: Working capital of $2.0 million; Plant, property and equipment of $193.5 million; Goodwill of $48.5 million; Other assets of $0.1 million; and Other long-term liabilities of $0.4 million. As the fair value paid for North Baja was greater than the recorded net assets of North Baja, the excess purchase price paid of $27.7 million was recorded as a reduction to Partners' Equity. The effect of recasting the Partnership's consolidated financial statements to account for the common control transaction increased the Partnership's net income by $8.3 million for the year ended December 31, 2009 from amounts previously reported.

Concurrent with the acquisition of North Baja, the Partnership entered into an exchange agreement with its General Partner whereby the Partnership issued 3,762,000 common units to the General Partner and provided for revised incentive distribution rights (Revised IDRs) in exchange for the cancellation of the incentive distribution rights available to the General Partner (Old IDRs) under the Amended and Restated Agreement of Limited Partnership of the Partnership.

Under the terms of the Revised IDRs, the distributions to the General Partner were reset to two percent, down from the General Partner distribution levels of the Old IDRs at 50 percent (for combined general partner interest and incentive distribution interest). The incentive distribution levels of the Revised IDRs will result in increased combined distributions to the General Partner (for general partner interest and incentive distribution interest) of 15 percent and a maximum of 25 percent when quarterly distributions increase to $0.81 and $0.88 per common unit or $3.24 and $3.52 per common unit on an annualized basis, respectively.

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 88-16
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51, 52
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Appendix F
-Paragraph F4
-Subparagraph e

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 67-73
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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CREDIT FACILITIES AND LONG-TERM DEBT

CREDIT FACILITIES AND LONG-TERM DEBT

12 Months Ended

Dec. 31, 2011

CREDIT FACILITIES AND LONG-TERM DEBT

NOTE 6 CREDIT FACILITIES AND LONG-TERM DEBT

December 31 (millions of dollars)	2011	2010


Senior Credit Facility due 2016	363.0	483.0
4.65% Senior Notes due 2021	349.4	–
6.89% Series C Senior Notes due 2012	3.1	3.9
3.82% Series D Senior Notes due 2017	27.0	27.0

	742.5	513.9
Less: current portion of long-term debt	3.1	483.8

	739.4	30.1

The Partnership's Senior Credit Facility consists of a $500.0 million senior revolving credit facility with a banking syndicate, maturing July 13, 2016, under which $363.0 million was outstanding at December 31, 2011 (2010 – $8.0 million), leaving $137.0 million available for future borrowing. At December 31, 2010 the senior credit facility also included a $475.0 million senior term loan of which $175.0 million was repaid on June 17, 2011 and the remaining $300.0 million was repaid on December 12, 2011.

On July 13, 2011, the Partnership closed an amendment to its Senior Credit Facility increasing the senior revolving credit facility from $250.0 million to $500.0 million, and extending the maturity date of the senior revolving credit facility to July 2016 from December 2011. At the Partnership's option, the interest rate on the outstanding borrowings under the senior revolving credit facility may be the lenders' base rate or the London Interbank Offered Rate (LIBOR) plus, in either case, an applicable margin that is based on the Partnership's long-term unsecured credit ratings. The Senior Credit Facility permits the Partnership to specify the portion of the borrowings to be covered by specific interest rate options and, for LIBOR-based borrowings, to specify the interest rate period. The Partnership is required to pay a commitment fee based on its credit rating and on the unused principal amount of the commitments under the senior revolving credit facility. The senior revolving credit facility has a feature whereby at any time, so long as no event of default has occurred and is continuing, the Partnership may request an increase in the senior revolving credit facility of up to $250.0 million, but no lender has an obligation to increase their respective share of the facility.

The interest rate on the Senior Credit Facility averaged 0.86 percent for the year ended December 31, 2011 (2010 – 0.91 percent). After hedging activity, the interest rate incurred on the Senior Credit Facility averaged 4.07 percent for the year ended December 31, 2011 (2010 – 4.30 percent). Prior to hedging activities, the interest rate was 1.65 percent at December 31, 2011 (2010 – 0.83 percent).

On June 17, 2011, the Partnership closed a $350.0 million public debt offering of 10-year, senior unsecured notes with an interest rate of 4.65 percent. Proceeds were used to repay funds borrowed under the Partnership's bridge loan facility and to partially repay borrowings under our existing Senior Credit Facility. The senior notes mature June 15, 2021. The indenture for the notes contains customary investment grade covenants.

On May 3, 2011, the Partnership entered into an agreement with SunTrust Robinson Humphrey, Inc., as Arranger, for a 364-day senior unsecured bridge loan facility for up to $400.0 million to fund the GTN and Bison Acquisitions. Borrowings under the bridge loan facility bore interest based, at the Partnership's election, on the lenders' base rate or the LIBOR plus in either case, an applicable margin. On May 3, 2011, the Partnership drew $61.0 million to partially fund the GTN and Bison Acquisitions. Please see Note 5 for more details on the Acquisitions. On June 17, 2011, the Partnership repaid the $61.0 million draw, and the bridge loan facility was cancelled. The interest rate on the loan made under the bridge loan facility was 1.7 percent.

At December 31, 2011, the Partnership was in compliance with its financial covenants, in addition to the other covenants which include restrictions on entering into mergers, consolidations and sales of assets, granting liens, material amendments to the second amended and restated agreement of limited partnership (Partnership Agreement), incurring additional debt and distributions to unitholders.

Series C and D Senior Notes are secured by Tuscarora's transportation contracts, supporting agreements and substantially all of Tuscarora's property. The note purchase agreements contain certain provisions that include, among other items, limitations on additional indebtedness and distributions to partners.

The principal repayments required on the long-term debt are as follows:

(millions of dollars)


2012		3.1
2013		3.5
2014		3.6
2015		3.7
2016		3.9
Thereafter		724.7

		742.5

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

FINANCIAL CHARGES AND OTHER

PARTNERS' EQUITY

12 Months Ended

Dec. 31, 2011

PARTNERS' EQUITY

PARTNERS' EQUITY

NOTE 7 PARTNERS' EQUITY

At December 31, 2011, Partners' equity included 53,472,766 common units (2010 – 46,227,766 common units) representing an aggregate 98 percent limited partner interest in the Partnership (including 5,797,106 common units held by the General Partner and 11,287,725 common units held indirectly by TransCanada) and an aggregate two percent general partner interest. In aggregate, the General Partner's interests represent an effective 12.6 percent ownership in the Partnership at December 31, 2011 (2010 – 14.3 percent).

On May 3, 2011, the Partnership completed a public offering of 7,245,000 common units at $47.58 per common unit for gross proceeds of $344.7 million and net proceeds of $330.9 after unit issuance costs. The General Partner maintained its effective two percent general partner interest in the Partnership by contributing $6.7 million to the Partnership in connection with the offering. See Note 5 for additional information regarding the equity issuance in connection with the Acquisitions.

On November 18, 2009, the Partnership completed a public offering of 5,000,000 common units at $38.00 per common unit for gross proceeds of $190.0 million and net proceeds of $181.8 million after unit issuance costs. The General Partner maintained its effective two percent general partner interest in the Partnership by contributing $3.8 million to the Partnership in connection with the offering. See Note 5 for disclosure regarding the equity issuance in connection with the acquisition of North Baja in 2009.

FINANCIAL CHARGES AND OTHER

12 Months Ended

Dec. 31, 2011

FINANCIAL CHARGES AND OTHER

NOTE 8 FINANCIAL CHARGES AND OTHER

Year ended December 31 (millions of dollars)	2011		2010		2009


Interest expense on long-term debt	13.9		8.4		12.5
Interest expense on short-term debt^(a)	–		–		2.1
Capitalized interest^(a)	–		(0.2	)	(0.4	)
Loss on interest rate swaps and options	13.6		16.5		15.1
Interest income^(a)	(1.5	)	–		(0.4	)
Amortization of debt issue costs	2.0		0.5		0.4
Other	–		0.4		–

	28.0		25.6		29.3

^(a): Recast as discussed in Notes 2 and 5.

NET INCOME PER COMMON UNIT

12 Months Ended

Dec. 31, 2011

NET INCOME PER COMMON UNIT

NET INCOME PER COMMON UNIT

NOTE 9 NET INCOME PER COMMON UNIT

Net income per common unit is computed by dividing net income, after deduction of the General Partner's allocation, by the weighted average number of common units outstanding. The General Partner's allocation is equal to an amount based upon the General Partner's effective two percent general partner interest, plus an amount equal to incentive distributions. Incentive distributions are paid to the General Partner if quarterly cash distributions on the common units exceed levels specified in the Partnership Agreement.

Net income per common unit was determined as follows:

(millions of dollars except per unit)		2011		2010		2009


Net income^(a)		157.4		137.1		106.1
North Baja's contribution prior to acquisition		–		–		(8.3	)

Net income allocated to partners^(b)		157.4		137.1		97.8
Net income allocated to General Partner:
	General partner interest	(3.1	)	(2.7	)	(1.9	)
	Incentive distribution income allocation	–		–		(5.3	)

		(3.1	)	(2.7	)	(7.2	)

Net income allocable to common units		154.3		134.4		90.6

Weighted average common units outstanding (millions)		51.1		46.2		38.7
Net income per common unit		$3.02		$2.91		$2.34

^(a): 2011 net income includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011. 2009 net income was recast as discussed in Notes 2 and 5.
^(b): Net income allocated to partners excludes North Baja's earnings prior to the Partnership's acquisition of North Baja on July 1, 2009, as the earnings of North Baja prior to that date were allocated to TransCanada and were not allocable to either the General Partner or common units.

CASH DISTRIBUTIONS

12 Months Ended

Dec. 31, 2011

CASH DISTRIBUTIONS

CASH DISTRIBUTIONS

NOTE 10 CASH DISTRIBUTIONS

The Partnership makes cash distributions to its partners with respect to each calendar quarter within 45 days after the end of each quarter. Distributions are based on Available Cash, as defined in the Partnership Agreement, which includes all cash and cash equivalents of the Partnership and working capital borrowings less reserves established by the General Partner. The unitholders currently receive a quarterly distribution of $0.77 per common unit if and to the extent there is sufficient Available Cash.

As an incentive, the General Partner's percentage interest in quarterly distributions is increased after certain specified target levels are met. Prior to July 1, 2009, the combined general partner interest and incentive distribution interest payable to the General Partner were 15 percent, 25 percent, and 50 percent of all quarterly distributions of Available Cash that exceed target levels of $0.45, $0.5275 and $0.69 per common unit, respectively. On July 1, 2009, the incentive distributions were revised under the Second Amended and Restated Agreement of Limited Partnership of the Partnership. Currently, the combined general partner interest and incentive distribution interest payable to the General Partner are 15 percent and a maximum of 25 percent of all quarterly distributions of Available Cash that exceed target levels of $0.81 and $0.88, respectively, per common unit.

For the year ended December 31, 2011, the Partnership distributed $3.04 per common unit (2010 – $2.94 per common unit; 2009 – $2.87 per common unit) for a total of $154.8 million (2010 – $138.7 million; 2009 – $117.0 million). The distributions paid for the year ended December 31, 2011 included no incentive distributions to the General Partner (2010 – $nil; 2009 – $5.3 million). Partnership income is allocated to the General Partner and the limited partners in accordance with their respective partnership percentages, after giving effect to any priority income allocations for incentive distributions that are allocated 100 percent to the General Partner.

CHANGE IN WORKING CAPITAL

12 Months Ended

Dec. 31, 2011

CHANGE IN WORKING CAPITAL

CHANGE IN WORKING CAPITAL

NOTE 11 CHANGE IN WORKING CAPITAL

Year Ended December 31 (millions of dollars)	2011		2010		2009^(a)


(Increase)/decrease in accounts receivable and other	(0.1	)	(0.1	)	2.8
(Decrease)/increase in accounts payable and accrued liabilities	(2.7	)	3.2		(0.8	)
Decrease in accrued interest	(0.2	)	–		(2.4	)

	(3.0	)	3.1		(0.4	)
Increase in investing working capital	–		–		(2.9	)

(Increase)/decrease in operating working capital	(3.0	)	3.1		2.5

^(a): Recast as discussed in Notes 2 and 5.

RELATED PARTY TRANSACTIONS

12 Months Ended

Dec. 31, 2011

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS

NOTE 12 RELATED PARTY TRANSACTIONS

The Partnership does not have any employees. The management and operating functions are provided by the General Partner. The General Partner does not receive a management fee in connection with its management of the Partnership. The Partnership reimburses the General Partner for all costs of services provided, including the costs of employee, officer and director compensation and benefits, and all other expenses necessary or appropriate to the conduct of the business of, and allocable to, the Partnership. Such costs include (i) overhead costs (such as office space and equipment) and (ii) out-of-pocket expenses related to the provision of such services. The Partnership Agreement provides that the General Partner will determine the costs that are allocable to the Partnership in any reasonable manner determined by the General Partner in its sole discretion. Total costs charged to the Partnership by the General Partner were $2.2 million for the year ended December 31, 2011 (2010 – $2.2 million; 2009 – $2.1 million).

As operator, TransCanada's subsidiaries provide capital and operating services to Great Lakes, Northern Border, GTN, Bison, North Baja and Tuscarora (together, "our pipeline systems"). TransCanada's subsidiaries incur costs on behalf of our pipeline systems, including, but not limited to, employee salary and benefit costs, and property and liability insurance costs.

Capital and operating costs charged to our pipeline systems for the years ended December 31, 2011, 2010 and 2009 by TransCanada's subsidiaries and amounts payable to TransCanada's subsidiaries at December 31, 2011 and 2010 are summarized in the following tables:

Year ended December 31 (millions of dollars)		2011	2010	2009


Capital and operating costs charged by TransCanada's subsidiaries to:
	Great Lakes	31.2	30.3	33.8
	Northern Border	28.7	25.8	25.5
	GTN^(a)	22.3	–	–
	Bison^(a)	7.7	–	–
	North Baja^(b)	3.7	4.4	2.9
	Tuscarora	4.7	3.7	3.0
Impact on the Partnership's net income:
	Great Lakes	14.1	12.8	14.3
	Northern Border	13.4	12.5	12.3
	GTN^(a)	21.2	–	–
	Bison^(a)	4.3	–	–
	North Baja^(b)	3.5	3.2	2.4
	Tuscarora	4.6	3.5	2.8

December 31 (millions of dollars)		2011	2010


Amount payable to TransCanada's subsidiaries for costs charged in the year by:
	Great Lakes	3.1	3.0
	Northern Border	2.9	2.2
	GTN^(a)	3.0	–
	Bison^(a)	1.0	–
	North Baja	0.5	0.6
	Tuscarora	0.6	0.7

^(a): Represents operations from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
^(b): Recast as discussed in Notes 2 and 5.

Great Lakes earns transportation revenues from TransCanada and its affiliates under contracts, some of which are provided at discounted rates and some at maximum recourse rates. The contracts have remaining terms ranging from one to six years. Great Lakes earned $80.6 million of transportation revenues under these contracts in 2011 (2010 – $148.5 million; 2009 – $141.7 million). This amount represents 32.2 percent of total revenues earned by Great Lakes in 2011 (2010 – 56.6 percent; 2009 – 48.9 percent).Great Lakes also earned $1.3 million in affiliated rental revenue in 2011 (2010 – $0.9 million; 2009 – $0.6 million).

Revenue from TransCanada and its affiliates of $38.0 million is included in the Partnership's equity income from Great Lakes in 2011 (2010 – $69.3 million; 2009 – $66.1 million). At December 31, 2011, $7.1 million was included in Great Lakes' receivables in regards to the transportation contracts with TransCanada and its affiliates (2010 – $11.0 million).

The entire disclosure for related party transactions, including the nature of the relationship(s), a description of the transactions, the amount of the transactions, the effects of any change in the method of establishing the terms of the transaction from the previous period, stated interest rate, expiration date, terms and manner of settlement per the agreement with the related party, and amounts due to or from related parties. If the entity and one or more other entities are under common ownership or management control and this control affects the operating results or financial position, disclosure includes the nature of the control relationship even if there are no transactions between the entities. Disclosure may also include the aggregate amount of current and deferred tax expense for each statement of earnings presented where the entity is a member of a group that files a consolidated tax return, the amount of any tax related balances due to or from affiliates as of the date of each statement of financial position presented, the principal provisions of the method by which the consolidated amount of current and deferred tax expense is allocated to the members of the group and the nature and effect of any changes in that method. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph k

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 3A
-Section 04
-Paragraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 1-4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39691-107864

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39678-107864

QUARTERLY FINANCIAL DATA (unaudited)

QUARTERLY FINANCIAL DATA (unaudited)

12 Months Ended

Dec. 31, 2011

QUARTERLY FINANCIAL DATA (unaudited)

NOTE 13 QUARTERLY FINANCIAL DATA (unaudited)

The following sets forth selected unaudited financial data for the four quarters in 2011 and 2010:

Quarter ended (millions of dollars except per common unit amounts)	Mar 31	Jun 30	Sep 30	Dec 31


2011
Equity income^(a)	38.6	37.5	40.4	37.0
Transmission revenues	17.3	17.6	17.6	17.9
Net income^(a)	42.3	36.1	40.7	38.3
Net income per common unit	$0.90	$0.69	$0.75	$0.70
Cash distributions paid	35.4	35.4	42.0	42.0

2010
Equity income	30.9	25.3	35.6	34.2
Transmission revenues	17.4	17.0	17.4	17.3
Net income	33.7	27.7	38.6	37.1
Net income per common unit	$0.71	$0.59	$0.82	$0.79
Cash distributions paid	34.4	34.4	34.4	35.4

^(a): Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.

The entire disclosure for the quarterly financial data in the annual financial statements. The disclosure may include a tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income or loss before extraordinary items and earnings per share data. It also includes an indication if the information in the note is unaudited, comments on the aggregate effect of year-end adjustments, and an explanation of matters or transactions that affect comparability or are pertinent to an understanding of the information furnished.

ACCOUNTS RECEIVABLE AND OTHER

FINANCIAL INSTRUMENTS

12 Months Ended

Dec. 31, 2011

FINANCIAL INSTRUMENTS.

FINANCIAL INSTRUMENTS

NOTE 14 FINANCIAL INSTRUMENTS

The carrying value of cash and cash equivalents, accounts receivable and other, accounts payable and accrued liabilities, and accrued interest approximate their fair values because of the short maturity or duration of these instruments, or because the instruments bear a variable rate of interest or a rate that approximates current rates. The fair value of the Partnership's long-term debt is estimated by discounting the future cash flows of each instrument at estimated current borrowing rates.

The estimated fair values of the Partnership's and its subsidiary's long-term debt as of December 31, 2011 and 2010 are as follows:

	2011		2010

December 31 (millions of dollars)	Carrying Value	Fair Value	Carrying Value	Fair Value

Senior Credit Facility	363.0	363.0	483.0	483.0
Senior Notes	349.4	367.7	–	–
Series C Senior Notes	3.1	3.3	3.9	4.3
Series D Senior Notes	27.0	29.4	27.0	26.6

	742.5	763.4	513.9	513.9

The Partnership's long-term debt results in exposures to changing interest rates. Until December 12, 2011, the Partnership used derivatives to assist in managing its exposure to interest rate risk.

The interest rate swaps and options were structured such that the cash flows matched those of the Senior Credit Facility. There were no amounts hedged at December 31, 2011 (2010 – $375.0 million). $300.0 million of variable-rate debt was hedged by an interest rate swap through December 12, 2011, where the fixed interest rate paid was 4.89 percent. $75.0 million of variable-rate debt was hedged by an interest rate swap through February 28, 2011, where the fixed interest rate paid was 3.86 percent. In addition to these fixed rates, the Partnership paid an applicable margin in accordance with the Senior Credit Facility agreement.

Financial instruments are recorded at fair value on a recurring basis and are categorized into one of three categories based upon a fair value hierarchy. The Partnership has classified all of its derivative financial instruments as Level II for all periods presented where the fair value is determined by using valuation techniques that refer to observable market data or estimated market prices. At December 31, 2011, the fair value of the interest rate swaps accounted for as hedges was nil (2010 – $13.8 million current liability). In 2011, the Partnership recorded interest expense of $13.6 million on the interest rate swaps and options (2010 – $16.5 million; 2009 – $15.1 million).

ACCOUNTS RECEIVABLE AND OTHER

12 Months Ended

Dec. 31, 2011

ACCOUNTS RECEIVABLE AND OTHER

NOTE 15 ACCOUNTS RECEIVABLE AND OTHER

December 31 (millions of dollars)	2011	2010


Accounts receivable	7.6	7.6
Inventory	0.9	0.7
Prepayments	0.3	0.4

	8.8	8.7

REGULATORY MATTERS

12 Months Ended

Dec. 31, 2011

REGULATORY MATTERS

REGULATORY MATTERS

NOTE 16 REGULATORY MATTERS

On May 24, 2011, the FERC issued an order initiating an investigation pursuant to Section 5 of the NGA to determine whether Tuscarora's existing rates for jurisdictional services were unjust and unreasonable. The FERC initiated this proceeding following a complaint filed by the Public Utilities Commission of Nevada (PUCN) and Sierra Pacific Power Company d/b/a NV Energy (NV Energy). On December 23, 2011, Tuscarora filed a petition with the FERC requesting approval of a Stipulation and Agreement of Settlement (Tuscarora Settlement), resolving all issues, raised in the Section 5 proceeding. On February 6, 2012, the Administrative Law Judge assigned to the case certified the settlement proposal and made a recommendation that the FERC approve the settlement. The settlement includes three year contract extensions to the term of a number of contracts with Tuscarora's largest customer. If approved, the rates will be effective January 1, 2012, and a moratorium on the filing of future rate proceedings under NGA Sections 4 or 5 will extend until December 31, 2014. Pursuant to the settlement, Tuscarora will have no future obligation to file a Section 4 rate case. A decision from the FERC is pending.

SUBSEQUENT EVENTS

12 Months Ended

Dec. 31, 2011

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS

NOTE 17 SUBSEQUENT EVENTS

On January 17, 2012, the board of directors of our General Partner declared the Partnership's fourth quarter 2011 cash distribution in the amount of $0.77 per common unit. The fourth quarter cash distribution, which was paid on February 14, 2012 to unitholders of record as of January 31, 2012, totaled $42.0 million and was paid in the following manner: $41.2 million to common unitholders (including $4.5 million to the General Partner as holder of 5,797,106 common units and $8.7 million to TransCanada as holder of 11,287,725 common units) and $0.8 million to the General Partner in respect of its two percent general partner interest.

Great Lakes declared its fourth quarter 2011 distribution of $23.3 million on January 11, 2012, of which the Partnership received its 46.45 percent share or $10.8 million. The distribution was paid on February 1, 2012.

Northern Border declared and paid its fourth quarter 2011 distribution of $50.0 million on February 1, 2012, of which the Partnership received its 50 percent share or $25.0 million.

GTN declared and paid its fourth quarter 2011 distribution of $21.4 million on February 1, 2012, of which the Partnership received its 25 percent share or $5.4 million.

Bison declared its fourth quarter 2011 distribution of $15.6 million on January 11, 2012, of which the Partnership received its 25 percent share or $3.9 million. The distribution was paid on February 1, 2012.

SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2011

SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

(a) Basis of Presentation

Amounts are stated in U.S. dollars.

Acquisitions

(b) Acquisitions

Use of Estimates

(c) Use of Estimates

Cash and Cash Equivalents

(d) Cash and Cash Equivalents

The Partnership's short-term investments with original maturities of three months or less are considered to be cash equivalents and are recorded at cost, which approximates market value.

Plant, Property and Equipment

(e) Plant, Property and Equipment

Long-lived Assets

(f) Long-lived Assets

Partners' Equity

(g) Partners' Equity

Costs incurred in connection with the issuance of units are deducted from the proceeds received.

Revenue Recognition

(h) Revenue Recognition

Income Taxes

(i) Income Taxes

Acquisitions and Goodwill

(j) Acquisitions and Goodwill

Derivative Financial Instruments and Hedging Activities

(k) Derivative Financial Instruments and Hedging Activities

Asset Retirement Obligation

(l) Asset Retirement Obligation

Government Regulation

(m) Government Regulation

Debt Issuance Costs

(n) Debt Issuance Costs

Costs related to the issuance of debt are deferred and amortized using the effective interest rate method over the term of the related debt.

INVESTMENTS IN UNCONSOLIDATED AFFILIATES (Tables)

12 Months Ended

Dec. 31, 2011

INVESTMENTS IN UNCONSOLIDATED AFFILIATES

Schedule of equity method investments in unconsolidated affiliates

		Equity Earnings from Unconsolidated Affiliates			Investment in Unconsolidated Affiliates

		Year Ended December 31			December 31
	Ownership Interest at December 31, 2011	Year Ended December 31			December 31
(unaudited) (millions of dollars)	Ownership Interest at December 31, 2011	2011	2010	2009	2011	2010

Great Lakes	46.45%	59.5	58.7	59.1	685.5	690.0
Northern Border^(a)	50%	75.5	67.3	40.3	536.1	504.8
GTN^(b)	25%	11.5	–	–	225.1	–
Bison^(b)	25%	7.0	–	–	162.8	–

		153.5	126.0	99.4	1,609.5	1,194.8

(a): Equity income from Northern Border is net of the 12-year amortization of a $10 million transaction fee paid to the operator of Northern Border at the time of the Partnership's additional 20 percent acquisition in April 2006.
(b): Represents equity earnings from May 3, 2011, date of acquisition, to December 31, 2011.

Great Lakes

Summarized financial information for equity method investment

December 31 (millions of dollars)	2011	2010


Assets
Current assets	65.3	83.7
Plant, property and equipment, net	826.2	846.9
Other assets	0.6	0.6

	892.1	931.2

Liabilities and Partners' Equity
Current liabilities	30.0	34.9
Deferred credits	0.4	5.6
Long-term debt, including current maturities	373.0	392.0
Partners' capital	488.7	498.7

	892.1	931.2

Year ended December 31 (millions of dollars)	2011		2010		2009


Transmission revenues	250.0		262.4		289.7
Operating expenses	(61.8	)	(59.2	)	(66.5	)
Depreciation	(32.2	)	(40.5	)	(58.5	)
Financial charges and other	(29.9	)	(30.9	)	(31.9	)
Michigan business tax	1.9		(5.3	)	(5.4	)

Net income	128.0		126.5		127.4

Northern Border

Summarized financial information for equity method investment

December 31 (millions of dollars)		2011		2010


Assets
Cash and cash equivalents		32.8		10.2
Other current assets		35.6		37.1
Plant, property and equipment, net		1,266.6		1,294.8
Other assets		31.4		22.9

		1,366.4		1,365.0

Liabilities and Partners' Equity
Current liabilities		48.6		46.7
Deferred credits and other		12.8		9.7
Long-term debt, including current maturities		472.6		540.6
Partners' equity
	Partners' capital	835.1		770.9
	Accumulated other comprehensive loss	(2.7	)	(2.9	)

		1,366.4		1,365.0

Year ended December 31 (millions of dollars)	2011		2010		2009


Transmission revenues	310.1		295.1		249.2
Operating expenses	(73.2	)	(74.0	)	(70.8	)
Depreciation	(61.6	)	(61.5	)	(61.9	)
Financial charges and other	(22.6	)	(23.4	)	(34.4	)

Net income	152.7		136.2		82.1

GTN

Summarized financial information for equity method investment

December 31 (millions of dollars)		2011


Assets
Current assets		54.6
Plant, property and equipment, net		1,207.2
Other assets		1.1

		1,262.9

Liabilities and Members' Equity
Current liabilities		17.7
Deferred credits and other		19.7
Long-term debt, including current maturities		325.0
Members' capital		900.5

		1,262.9

For the period May 3 to December 31, 2011 (millions of dollars)


Transmission revenues	133.2
Operating expenses	(36.7	)
Depreciation	(36.2	)
Financial charges and other	(15.0	)

Net income	45.3

Bison

Summarized financial information for equity method investment

December 31 (millions of dollars)		2011


Assets
Current assets		9.9
Plant, property and equipment, net		657.9
Other assets		–

		667.8

Liabilities and Members' Equity
Current liabilities		16.8
Members' capital		651.0

		667.8

For the period May 3 to December 31, 2011 (millions of dollars)


Transmission revenues	51.8
Operating expenses	(11.3	)
Depreciation	(12.4	)

Net income	28.1

PLANT, PROPERTY AND EQUIPMENT (Tables)

12 Months Ended

Dec. 31, 2011

PLANT, PROPERTY AND EQUIPMENT

Schedule of plant, property and equipment

	2011			2010

December 31 (millions of dollars)	Cost	Accumulated Depreciation	Net Book Value	Cost	Accumulated Depreciation	Net Book Value

Pipeline	290.0	110.0	180.0	290.1	100.6	189.5
Compression	104.8	19.5	85.3	113.4	24.5	88.9
Metering and other	42.4	9.3	33.1	42.2	8.2	34.0
Under construction	0.1	–	0.1	0.2	–	0.2

	437.3	138.8	298.5	445.9	133.3	312.6

CREDIT FACILITIES AND LONG-TERM DEBT (Tables)

12 Months Ended

Dec. 31, 2011

CREDIT FACILITIES AND LONG-TERM DEBT

Components of debt

December 31 (millions of dollars)	2011	2010


Senior Credit Facility due 2016	363.0	483.0
4.65% Senior Notes due 2021	349.4	–
6.89% Series C Senior Notes due 2012	3.1	3.9
3.82% Series D Senior Notes due 2017	27.0	27.0

	742.5	513.9
Less: current portion of long-term debt	3.1	483.8

	739.4	30.1

Principal repayments required on long-term debt

(millions of dollars)


2012		3.1
2013		3.5
2014		3.6
2015		3.7
2016		3.9
Thereafter		724.7

		742.5

FINANCIAL CHARGES AND OTHER (Tables)

12 Months Ended

Dec. 31, 2011

FINANCIAL CHARGES AND OTHER

Schedule of Financial Charges and Other

Year ended December 31 (millions of dollars)	2011		2010		2009


Interest expense on long-term debt	13.9		8.4		12.5
Interest expense on short-term debt^(a)	–		–		2.1
Capitalized interest^(a)	–		(0.2	)	(0.4	)
Loss on interest rate swaps and options	13.6		16.5		15.1
Interest income^(a)	(1.5	)	–		(0.4	)
Amortization of debt issue costs	2.0		0.5		0.4
Other	–		0.4		–

	28.0		25.6		29.3

^(a): Recast as discussed in Notes 2 and 5.

NET INCOME PER COMMON UNIT (Tables)

12 Months Ended

Dec. 31, 2011

NET INCOME PER COMMON UNIT

Schedule of net income per common unit

(millions of dollars except per unit)		2011		2010		2009


Net income^(a)		157.4		137.1		106.1
North Baja's contribution prior to acquisition		–		–		(8.3	)

Net income allocated to partners^(b)		157.4		137.1		97.8
Net income allocated to General Partner:
	General partner interest	(3.1	)	(2.7	)	(1.9	)
	Incentive distribution income allocation	–		–		(5.3	)

		(3.1	)	(2.7	)	(7.2	)

Net income allocable to common units		154.3		134.4		90.6

Weighted average common units outstanding (millions)		51.1		46.2		38.7
Net income per common unit		$3.02		$2.91		$2.34

^(a): 2011 net income includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011. 2009 net income was recast as discussed in Notes 2 and 5.
^(b): Net income allocated to partners excludes North Baja's earnings prior to the Partnership's acquisition of North Baja on July 1, 2009, as the earnings of North Baja prior to that date were allocated to TransCanada and were not allocable to either the General Partner or common units.

CHANGE IN WORKING CAPITAL (Tables)

12 Months Ended

Dec. 31, 2011

CHANGE IN WORKING CAPITAL

CHANGE IN WORKING CAPITAL

Year Ended December 31 (millions of dollars)	2011		2010		2009^(a)


(Increase)/decrease in accounts receivable and other	(0.1	)	(0.1	)	2.8
(Decrease)/increase in accounts payable and accrued liabilities	(2.7	)	3.2		(0.8	)
Decrease in accrued interest	(0.2	)	–		(2.4	)

	(3.0	)	3.1		(0.4	)
Increase in investing working capital	–		–		(2.9	)

(Increase)/decrease in operating working capital	(3.0	)	3.1		2.5

^(a): Recast as discussed in Notes 2 and 5.

RELATED PARTY TRANSACTIONS (Tables)

12 Months Ended

Dec. 31, 2011

RELATED PARTY TRANSACTIONS

Schedule of costs charged by related party

Year ended December 31 (millions of dollars)		2011	2010	2009


Capital and operating costs charged by TransCanada's subsidiaries to:
	Great Lakes	31.2	30.3	33.8
	Northern Border	28.7	25.8	25.5
	GTN^(a)	22.3	–	–
	Bison^(a)	7.7	–	–
	North Baja^(b)	3.7	4.4	2.9
	Tuscarora	4.7	3.7	3.0
Impact on the Partnership's net income:
	Great Lakes	14.1	12.8	14.3
	Northern Border	13.4	12.5	12.3
	GTN^(a)	21.2	–	–
	Bison^(a)	4.3	–	–
	North Baja^(b)	3.5	3.2	2.4
	Tuscarora	4.6	3.5	2.8

Schedule of amounts payable to related party for costs charged during the period

December 31 (millions of dollars)		2011	2010


Amount payable to TransCanada's subsidiaries for costs charged in the year by:
	Great Lakes	3.1	3.0
	Northern Border	2.9	2.2
	GTN^(a)	3.0	–
	Bison^(a)	1.0	–
	North Baja	0.5	0.6
	Tuscarora	0.6	0.7

^(a): Represents operations from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
^(b): Recast as discussed in Notes 2 and 5.

QUARTERLY FINANCIAL DATA (unaudited) (Tables)

12 Months Ended

Dec. 31, 2011

QUARTERLY FINANCIAL DATA (unaudited)

Schedule of quarterly financial data

Quarter ended (millions of dollars except per common unit amounts)	Mar 31	Jun 30	Sep 30	Dec 31


2011
Equity income^(a)	38.6	37.5	40.4	37.0
Transmission revenues	17.3	17.6	17.6	17.9
Net income^(a)	42.3	36.1	40.7	38.3
Net income per common unit	$0.90	$0.69	$0.75	$0.70
Cash distributions paid	35.4	35.4	42.0	42.0

2010
Equity income	30.9	25.3	35.6	34.2
Transmission revenues	17.4	17.0	17.4	17.3
Net income	33.7	27.7	38.6	37.1
Net income per common unit	$0.71	$0.59	$0.82	$0.79
Cash distributions paid	34.4	34.4	34.4	35.4

^(a): Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.

FINANCIAL INSTRUMENTS (Tables)

12 Months Ended

Dec. 31, 2011

FINANCIAL INSTRUMENTS.

Schedule of carrying value and fair value of long-term debt

	2011		2010

December 31 (millions of dollars)	Carrying Value	Fair Value	Carrying Value	Fair Value

Senior Credit Facility	363.0	363.0	483.0	483.0
Senior Notes	349.4	367.7	–	–
Series C Senior Notes	3.1	3.3	3.9	4.3
Series D Senior Notes	27.0	29.4	27.0	26.6

	742.5	763.4	513.9	513.9

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 14
-Subparagraph a
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15
-Subparagraph b-d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph a, c(1), c(2), c(3), d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph c(2), d, e, f
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 19
-Subparagraph a, b, c(1), d(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13467-108611

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13476-108611

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6447952&loc=d3e13220-108610

Schedule of accounts receivable and other

ACCOUNTS RECEIVABLE AND OTHER (Tables)

12 Months Ended

Dec. 31, 2011

ACCOUNTS RECEIVABLE AND OTHER

December 31 (millions of dollars)	2011	2010


Accounts receivable	7.6	7.6
Inventory	0.9	0.7
Prepayments	0.3	0.4

	8.8	8.7

ORGANIZATION (Details) - miles	12 Months Ended
ORGANIZATION (Details) - miles	Dec. 31, 2011	Feb. 02, 2012
Great Lakes
Organization
Ownership interest (as a percent)	46.45%	46.45%
Length of the pipeline owned by equity method investee (in miles)	2,115
Northern Border
Organization
Ownership interest (as a percent)	50.00%	50.00%
Length of the pipeline owned by equity method investee (in miles)	1,407
GTN
Organization
Ownership interest (as a percent)	25.00%	25.00%
Length of the pipeline owned by equity method investee (in miles)	1,353
Bison
Organization
Ownership interest (as a percent)	25.00%	25.00%
Length of the pipeline owned by equity method investee (in miles)	303
North Baja Pipeline, LLC
Organization
Partnership interest held (as a percent)	100.00%
Length of the pipeline owned by equity method investee (in miles)	86
Tuscarora Gas Transmission Company
Organization
Partnership interest held (as a percent)	100.00%
Length of the pipeline owned by equity method investee (in miles)	305

ORGANIZATION (Details 2) - shares	1 Months Ended			12 Months Ended
ORGANIZATION (Details 2) - shares	Feb. 29, 2012	May 31, 2011	Nov. 30, 2009	Dec. 31, 2011	Dec. 31, 2010	Jan. 31, 2012	Dec. 31, 2009
Common units and interest in the partnership
Number of common units owned				53,500,000	46,200,000		46,200,000
General Partner
Common units and interest in the partnership
General partner ownership interest in the partnership (as a percent)	2.00%	2.00%	2.00%	2.00%
Number of common units owned				5,797,106		5,797,106
Aggregate ownership interest in the Partnership (as a percent)				12.60%	14.30%
TransCanada Corporation
Common units and interest in the partnership
Number of common units owned				11,287,725		11,287,725
Limited partner interest (as a percent)				20.70%
Aggregate ownership interest in the Partnership (as a percent)				33.30%

SIGNIFICANT ACCOUNTING POLICIES (Details) - M	1 Months Ended		12 Months Ended
SIGNIFICANT ACCOUNTING POLICIES (Details) - M	May 31, 2011	Jul. 31, 2009	Dec. 31, 2011
Cash and Cash Equivalents
Maximum term of original maturity to classify instruments as cash equivalents (in months)			3
GTN
Acquisitions
Interest acquired by the Partnership (as a percent)	25.00%
Bison
Acquisitions
Interest acquired by the Partnership (as a percent)	25.00%
North Baja Pipeline, LLC
Acquisitions
Interest acquired by the Partnership (as a percent)		100.00%

SIGNIFICANT ACCOUNTING POLICIES (Details 2)	12 Months Ended
SIGNIFICANT ACCOUNTING POLICIES (Details 2)	Dec. 31, 2011 Y
Pipeline and compression
PLANT, PROPERTY AND EQUIPMENT
Estimated useful life, minimum (in years)	20
Estimated useful life, maximum (in years)	30
Metering and other
PLANT, PROPERTY AND EQUIPMENT
Estimated useful life, minimum (in years)	5
Estimated useful life, maximum (in years)	30

SIGNIFICANT ACCOUNTING POLICIES (Details 3) - USD ($) $ in Millions	Dec. 31, 2011	Dec. 31, 2010
Tuscarora Gas Transmission Company
Government Regulation
Regulatory liabilities	$ 0.2	$ 0.5

INVESTMENTS IN UNCONSOLIDATED AFFILIATES (Details)
$ in Millions

1 Months Ended

3 Months Ended

12 Months Ended

Apr. 30, 2006

USD ($)

Dec. 31, 2011

USD ($)

Sep. 30, 2011

USD ($)

Jun. 30, 2011

USD ($)

Mar. 31, 2011

USD ($)

Dec. 31, 2010

USD ($)

Sep. 30, 2010

USD ($)

Jun. 30, 2010

USD ($)

Mar. 31, 2010

USD ($)

Dec. 31, 2011

USD ($)

Dec. 31, 2010

USD ($)

Dec. 31, 2009

USD ($)

May 03, 2011

Feb. 28, 2007

$ 37.0

$ 40.4

$ 37.5

$ 38.6

$ 34.2

$ 35.6

$ 25.3

$ 30.9

$ 153.5

^[1]

$ 126.0

^[1]

$ 99.4

^[1]

TC GL Intermediate Limited Partnership

$ 1,609.5

1,194.8

$ 1,609.5

1,194.8

Partnership interest held (as a percent)

98.9899%

TC PipeLines Intermediate Limited Partnership

Partnership interest held (as a percent)

98.9899%

Great Lakes

Ownership interest at the end of the period (as a percent)

46.45%

$ 59.5

58.7

59.1

Amount of difference between the carrying value and the underlying equity in net assets resulting from the recognition and inclusion of goodwill

$ 685.5

690.0

685.5

690.0

458.4

Equity contribution

4.6

4.2

8.9

9.3

0.1

Total cash call issued by Great Lakes to fund its debt repayment

10.0

$ 9.0

Assets

Current assets

65.3

83.7

65.3

83.7

826.2

846.9

826.2

846.9

Other assets

0.6

892.1

931.2

892.1

931.2

Deferred credits and other

30.0

34.9

30.0

34.9

0.4

5.6

0.4

5.6

Long-term debt, including current maturities

373.0

392.0

373.0

392.0

488.7

498.7

488.7

498.7

$ 892.1

931.2

892.1

931.2

250.0

262.4

289.7

(61.8)

(59.2)

(66.5)

Financial charges and other

(32.2)

(40.5)

(58.5)

(29.9)

(30.9)

(31.9)

Michigan business tax

1.9

(5.3)

(5.4)

Great Lakes | TransCanada Corporation

$ 128.0

126.5

127.4

Limited partnership interest (as a percent)

53.55%

Northern Border

Ownership interest at the end of the period (as a percent)

50.00%

$ 75.5

67.3

40.3

Amortization period of transaction fee (in years) | Y

$ 536.1

504.8

$ 536.1

504.8

Transaction fee

$ 10.0

Additional ownership interest acquired (as a percent)

20.00%

Amount of difference between the carrying value and the underlying equity in net assets resulting from the recognition and inclusion of goodwill

119.9

120.8

$ 119.9

120.8

Equity contribution

5.0

$ 49.8

54.8

42.3

Assets

Cash and cash equivalents

32.8

10.2

32.8

10.2

Other current assets

35.6

37.1

35.6

37.1

1,266.6

1,294.8

1,266.6

1,294.8

Other assets

31.4

22.9

31.4

22.9

1,366.4

1,365.0

1,366.4

1,365.0

Deferred credits and other

48.6

46.7

48.6

46.7

12.8

9.7

12.8

9.7

Long-term debt, including current maturities

472.6

540.6

472.6

540.6

Accumulated other comprehensive loss

835.1

770.9

835.1

770.9

(2.7)

(2.9)

(2.7)

(2.9)

$ 1,366.4

$ 1,365.0

1,366.4

1,365.0

310.1

295.1

249.2

(73.2)

(74.0)

(70.8)

Financial charges and other

(61.6)

(61.5)

(61.9)

(22.6)

(23.4)

(34.4)

Northern Border | ONEOK Partners L.P.

$ 152.7

$ 136.2

$ 82.1

Limited partnership interest (as a percent)

50.00%

GTN

Ownership interest at the end of the period (as a percent)

25.00%

$ 11.5

$ 225.1

225.1

Assets

Current assets

54.6

1,207.2

Other assets

1.1

1,262.9

Deferred credits and other

17.7

19.7

Long-term debt, including current maturities

325.0

900.5

$ 1,262.9

1,262.9

133.2

(36.7)

Financial charges and other

(36.2)

(15.0)

$ 45.3

Bison

Ownership interest at the end of the period (as a percent)

25.00%

$ 7.0

Undistributed earnings

1.5

$ 162.8

162.8

Assets

Current assets

9.9

657.9

667.8

16.8

651.0

$ 667.8

667.8

51.8

(11.3)

(12.4)

$ 28.1

[1]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.

PLANT, PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Millions	Dec. 31, 2011	Dec. 31, 2010
PLANT, PROPERTY AND EQUIPMENT
Cost	$ 437.3	$ 445.9
Accumulated Depreciation	138.8	133.3
Net Book Value	298.5	312.6
Pipeline
PLANT, PROPERTY AND EQUIPMENT
Cost	290.0	290.1
Accumulated Depreciation	110.0	100.6
Net Book Value	180.0	189.5
Compression
PLANT, PROPERTY AND EQUIPMENT
Cost	104.8	113.4
Accumulated Depreciation	19.5	24.5
Net Book Value	85.3	88.9
Metering and other
PLANT, PROPERTY AND EQUIPMENT
Cost	42.4	42.2
Accumulated Depreciation	9.3	8.2
Net Book Value	33.1	34.0
Under construction
PLANT, PROPERTY AND EQUIPMENT
Cost	0.1	0.2
Net Book Value	$ 0.1	$ 0.2

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

Common units and interest in the partnership

ACQUISITIONS AND REVISED INCENTIVE DISTRIBUTION RIGHTS (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			12 Months Ended
	May 31, 2011	Nov. 30, 2009	Jul. 31, 2009	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Jul. 13, 2011	May 03, 2011	Mar. 25, 2011	Mar. 05, 2010	Jul. 02, 2009
Asset acquisition
Number of common units sold in public offering	7,245,000	5,000,000
Price per common unit issued (in dollars per unit)	$ 47.58	$ 38.00
Net proceeds from issuance of common units	$ 330.9	$ 181.8
Common units issued to TransCanada				7,300,000		11,300,000
Difference between purchase price and net assets acquired				$ 133.6	$ (0.1)	$ 27.7
Bridge loan facility
Asset acquisition
Outstanding borrowing capacity	$ 61.0
Maximum borrowing capacity								$ 400.0
Senior revolving credit facility
Asset acquisition
Maximum borrowing capacity							$ 500.0
GTN and Bison
Asset acquisition
Number of common units sold in public offering	7,245,000
Price per common unit issued (in dollars per unit)	$ 47.58
Net proceeds from issuance of common units	$ 330.9
Additional payment to TransCanada				23.5
Purchase price recorded as working capital				0.6
GTN and Bison \| Bridge loan facility
Asset acquisition
Amount drawn on credit facility to finance acquisition								61.0
Maximum borrowing capacity								400.0
GTN and Bison \| Senior revolving credit facility
Asset acquisition
Amount drawn on credit facility to finance acquisition								125.0
Maximum borrowing capacity								250.0
GTN and Bison \| TransCanada Subsidiaries
Asset acquisition
Purchase price								605.0
Contribution by General Partners	6.7
Cash on hand								15.1
Cash paid				538.7
Difference between purchase price and net assets acquired				131.2
GTN
Asset acquisition
Equity investment								$ 246.2
GTN \| TransCanada Subsidiaries
Asset acquisition
Interest acquired by the Partnership (as a percent)								25.00%
Purchase price								$ 405.0
Acquired debt								$ 81.3
Percentage of acquired debt								25.00%
Bison
Asset acquisition
Equity investment								$ 161.3
Bison \| TransCanada Subsidiaries
Asset acquisition
Interest acquired by the Partnership (as a percent)								25.00%
Purchase price								$ 200.0
Future commitments related to acquisitions	$ 9.1
Yuma Lateral Asset Acquisition \| TransCanada Corporation
Asset acquisition
Purchase price										$ 7.6
Equity investment				10.0
Cash paid									$ 2.4
Difference between purchase price and net assets acquired				2.3
Purchase price recorded as plant, property and equipment				$ 7.7
Yuma Lateral Asset Acquisition \| TransCanada Corporation \| Maximum
Asset acquisition
Future commitments related to acquisitions			$ 10.0
Payment to be made to TransCanada										$ 2.4
North Baja Acquisition \| Senior revolving credit facility
Asset acquisition
Amount drawn on credit facility to finance acquisition											$ 170.0
North Baja Acquisition \| TransCanada Corporation
Asset acquisition
Interest acquired by the Partnership (as a percent)											100.00%
Purchase price											$ 271.4
Common units issued to TransCanada			2,609,680
Price per common unit issued to TransCanada											$ 30.042
Net proceeds from issuance of common units to TransCanada											$ 78.4
Contribution by General Partners			$ 1.6
Cash on hand											21.4
Difference between purchase price and net assets acquired			$ 27.7
Purchase price recorded as working capital											2.0
Purchase price recorded as plant, property and equipment											193.5
Purchase price recorded as goodwill											48.5
Purchase price recorded as other assets											0.1
Purchase price recorded as Other long-term liabilities											$ 0.4
Increase in Partnership's net income						$ 8.3
North Baja Acquisition \| General Partner
Asset acquisition
General partner ownership interest in the partnership (as a percent)			2.00%

ACQUISITIONS AND REVISED INCENTIVE DISTRIBUTION RIGHTS (Details 2) - General Partner - $ / shares	1 Months Ended	12 Months Ended
	Jul. 31, 2009	Dec. 31, 2011	Jul. 02, 2009
Old IDRs
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	50.00%
Revised IDRs
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	2.00%
North Baja Acquisition \| Revised IDRs
Cash Distributions
Units issued			3,762,000
$0.81 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	25.00%
Target level of quarterly distributions (in dollars per common unit)			$ 0.81
$0.81 per common unit \| Revised IDRs
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold		15.00%
Target level of quarterly distributions (in dollars per common unit)		$ 0.81
$0.88 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	50.00%
Target level of quarterly distributions (in dollars per common unit)			$ 0.88
$0.88 per common unit \| Revised IDRs
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold		25.00%
Target level of quarterly distributions (in dollars per common unit)		$ 0.88
$3.24 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	25.00%
Target level of quarterly distributions, annualized basis (in dollars per common unit)	$ 3.24
$3.52 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	50.00%
Target level of quarterly distributions, annualized basis (in dollars per common unit)	$ 3.52

CREDIT FACILITIES AND LONG-TERM DEBT (Details) $ in Millions	1 Months Ended			12 Months Ended
	Jul. 31, 2011 USD ($)	Jun. 30, 2011 USD ($) Y	May 31, 2011 USD ($) D	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Jul. 13, 2011 USD ($)	May 03, 2011 USD ($)
Credit facility and long-term debt
Long-term debt				$ 742.5	$ 513.9
Less: current portion of long-term debt				3.1	483.8
Noncurrent portion of long-term debt				739.4	30.1
Senior Credit Facility due 2011 and 2016
Credit facility and long-term debt
Long-term debt				$ 363.0	$ 483.0
Debt average interest rate (as a percent)				0.86%	0.91%
Debt average interest rate, after hedging activity (as a percent)				4.07%	4.30%
Debt interest rate, at period end, prior to hedging activities (as a percent)				1.65%	0.83%
Senior term loan
Credit facility and long-term debt
Long-term debt					$ 475.0
Maximum borrowing capacity						$ 500.0
Repayment on borrowing		$ 175.0		$ 300.0
Line of credit facility, base rate	LIBOR
Senior revolving credit facility
Credit facility and long-term debt
Long-term debt				363.0	8.0
Maximum borrowing capacity						500.0
Maximum borrowing capacity before amendment						$ 250.0
Remaining borrowing capacity				137.0
Line of credit facility, base rate	LIBOR
Senior revolving credit facility \| Maximum
Credit facility and long-term debt
Option to increase borrowings on the credit facility	$ 250.0
3.82% Series D Senior Notes due 2017
Credit facility and long-term debt
Long-term debt				$ 27.0	27.0
Debt interest rate (as a percent)				3.82%
4.65% Senior Notes due 2021
Credit facility and long-term debt
Long-term debt				$ 349.4
Debt interest rate (as a percent)				4.65%
Public debt offering		$ 350.0
Debt offering term (in years) \| Y		10
6.89% Series C Senior Notes due 2012
Credit facility and long-term debt
Long-term debt				$ 3.1	$ 3.9
Debt interest rate (as a percent)				6.89%
Bridge loan facility
Credit facility and long-term debt
Maximum borrowing capacity							$ 400.0
Debt interest rate (as a percent)			1.70%
Line of credit facility, term (in days) \| D			364
Line of credit facility, base rate			LIBOR plus an applicable margin
Line of credit facility, repaid and cancelled			$ 61.0

CREDIT FACILITIES AND LONG-TERM DEBT (Details 2) - USD ($) $ in Millions	Dec. 31, 2011	Dec. 31, 2010
Principal repayments required on long-term debt
2012	$ 3.1
2013	3.5
2014	3.6
2015	3.7
2016	3.9
Thereafter	724.7
Total long-term debt	$ 742.5	$ 513.9

PARTNERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			12 Months Ended
	Feb. 29, 2012	May 31, 2011	Nov. 30, 2009	Dec. 31, 2011	Dec. 31, 2010	Jan. 31, 2012	Dec. 31, 2009
Public offering
Number of common units sold in public offering		7,245,000	5,000,000
Price per common unit in public offering (in dollars per unit)		$ 47.58	$ 38.00
Gross proceeds from public offering of common units		$ 344.7	$ 190.0
Net proceeds from public offering of common units		330.9	181.8
Common units and interest in the partnership
Number of common units owned				53,500,000	46,200,000		46,200,000
Limited Partners
Common units and interest in the partnership
Aggregate ownership interest in the Partnership (as a percent)				98.00%
Number of common units owned				53,472,766	46,227,766
General Partner
Common units and interest in the partnership
Capital contribution by general partner		$ 6.7	$ 3.8
Aggregate ownership interest in the Partnership (as a percent)				12.60%	14.30%
Number of common units owned				5,797,106		5,797,106
General partner ownership interest in the partnership (as a percent)	2.00%	2.00%	2.00%	2.00%
TransCanada Corporation
Common units and interest in the partnership
Aggregate ownership interest in the Partnership (as a percent)				33.30%
Number of common units owned				11,287,725		11,287,725

FINANCIAL CHARGES AND OTHER (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
FINANCIAL CHARGES AND OTHER
Interest expense on long-term debt	$ 13.9	$ 8.4	$ 12.5
Interest expense on short-term debt			2.1
Capitalized interest		0.2	0.4
Loss on interest rate swaps and options	13.6	16.5	15.1
Interest income	(1.5)		(0.4)
Amortization of debt issue costs	2.0	0.5	0.4
Other		0.4
Financial charges and other	$ 28.0	$ 25.6	$ 29.3

NET INCOME PER COMMON UNIT (Details)
shares in Millions, $ in Millions

1 Months Ended

3 Months Ended

12 Months Ended

Feb. 29, 2012

May 31, 2011

Nov. 30, 2009

Dec. 31, 2011

USD ($)

$ / shares

Sep. 30, 2011

USD ($)

$ / shares

Jun. 30, 2011

USD ($)

$ / shares

Mar. 31, 2011

USD ($)

$ / shares

Dec. 31, 2010

USD ($)

$ / shares

Sep. 30, 2010

USD ($)

$ / shares

Jun. 30, 2010

USD ($)

$ / shares

Mar. 31, 2010

USD ($)

$ / shares

Dec. 31, 2011

USD ($)

$ / shares

Dec. 31, 2010

USD ($)

$ / shares

Dec. 31, 2009

USD ($)

$ / shares

North Baja's contribution prior to acquisition

$ 38.3

$ 40.7

$ 36.1

$ 42.3

$ 37.1

$ 38.6

$ 27.7

$ 33.7

$ 157.4

^[1],[2]

$ 137.1

^[2]

$ 106.1

^[2],[3]

(8.3)

Net income allocated to partners

157.4

137.1

97.8

Net income allocated to General Partner:

General partner interest excluding Incentive distribution income

(3.1)

(2.7)

(1.9)

Incentive distribution income allocation

(5.3)

General partner interest

(3.1)

(2.7)

(7.2)

Net income allocable to common units

$ 154.3

$ 134.4

$ 90.6

Weighted average common units outstanding | shares

51.1

46.2

38.7

Net income per common unit (in dollars per unit) | $ / shares

0.70

0.75

0.69

0.90

0.79

0.82

0.59

0.71

3.02

2.91

2.34

General Partner

Common units and interest in the partnership

Additional percentage investment held by General Partner (as a percent)

2.00%

[1]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[2]	Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[3]	Recast as discussed in Notes 2 and 5.

CASH DISTRIBUTIONS (Details) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Jul. 31, 2009	Dec. 31, 2011 USD ($) $ / shares	Sep. 30, 2011 USD ($)	Jun. 30, 2011 USD ($)	Mar. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Sep. 30, 2010 USD ($)	Jun. 30, 2010 USD ($)	Mar. 31, 2010 USD ($)	Dec. 31, 2011 USD ($) D $ / shares	Dec. 31, 2010 USD ($) $ / shares	Dec. 31, 2009 USD ($) $ / shares	Jul. 02, 2009 $ / shares
CASH DISTRIBUTIONS
Number of days after the end of each quarter for making cash distribution \| D										45
Quarterly cash distributions (in dollars per unit)										$ 0.77
Cash Distributions
Cash distribution \| $		$ 42.0	$ 42.0	$ 35.4	$ 35.4	$ 35.4	$ 34.4	$ 34.4	$ 34.4
Incentive distributions to General Partner \| $												$ 5.3
General Partner
Cash Distributions
Cash distributions (in dollars per unit)										$ 3.04	$ 2.94	$ 2.87
Cash distribution \| $										$ 154.8	$ 138.7	$ 117.0
Incentive distributions to General Partner \| $												$ 5.3
Percentage of priority income allocations for incentive distributions										100.00%
General Partner \| $0.81 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	25.00%
Target level of quarterly distributions (in dollars per common unit)													$ 0.81
General Partner \| $0.88 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	50.00%
Target level of quarterly distributions (in dollars per common unit)													$ 0.88
General Partner \| Incentive Distribution Agreement prior to July 1, 2009
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	50.00%
General Partner \| Incentive Distribution Agreement prior to July 1, 2009 \| $0.45 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold										15.00%
Target level of quarterly distributions (in dollars per common unit)		$ 0.45								$ 0.45
General Partner \| Incentive Distribution Agreement prior to July 1, 2009 \| $0.5275 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold										25.00%
Target level of quarterly distributions (in dollars per common unit)		0.5275								$ 0.5275
General Partner \| Incentive Distribution Agreement prior to July 1, 2009 \| $0.69 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold										50.00%
Target level of quarterly distributions (in dollars per common unit)		0.69								$ 0.69
General Partner \| Incentive Distribution, as amended
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold	2.00%
General Partner \| Incentive Distribution, as amended \| $0.81 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold										15.00%
Target level of quarterly distributions (in dollars per common unit)		0.81								$ 0.81
General Partner \| Incentive Distribution, as amended \| $0.88 per common unit
Cash Distributions
Combined general partner interest and incentive distribution interest percentage of quarterly distributions of Available Cash exceeding target levels, threshold										25.00%
Target level of quarterly distributions (in dollars per common unit)		$ 0.88								$ 0.88

CHANGE IN WORKING CAPITAL (Details) - USD ($) $ in Millions	12 Months Ended
CHANGE IN WORKING CAPITAL (Details) - USD ($) $ in Millions	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CHANGE IN WORKING CAPITAL
(Increase)/decrease in accounts receivable and other	$ (0.1)	$ (0.1)	$ 2.8
(Decrease)/increase in accounts payable and accrued liabilities	(2.7)	3.2	(0.8)
Decrease in accrued interest	(0.2)		(2.4)
Change in working capital	(3.0)	3.1	(0.4)
Increase in investing working capital			(2.9)
(Increase)/decrease in operating working capital	$ (3.0)	$ 3.1	$ 2.5

RELATED PARTY TRANSACTIONS (Details) $ in Millions	12 Months Ended
RELATED PARTY TRANSACTIONS (Details) $ in Millions	Dec. 31, 2011 USD ($) Y	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)
General Partner
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	$ 2.2	$ 2.2	$ 2.1
TransCanada Corporation \| Great Lakes
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	31.2	30.3	33.8
Impact on the Partnership's net income	14.1	12.8	14.3
Amounts payable to TransCanada and its affiliates	3.1	3.0
Transportation revenues from TransCanada and its affiliates	$ 80.6	$ 148.5	$ 141.7
Percentage of transportation revenues to total revenues	32.20%	56.60%	48.90%
Affiliated rental revenue	$ 1.3	$ 0.9	$ 0.6
Revenue from TransCanada and its affiliates included in the Partnership's equity income from Great Lakes	38.0	69.3	66.1
Great Lakes' receivables for transportation contracts with TransCanada and its affiliates	$ 7.1	11.0
TransCanada Corporation \| Great Lakes \| Minimum
Costs charged to the pipeline system and amounts payable
TransCanada and its affiliates contracts' remaining term (in years) \| Y	1
TransCanada Corporation \| Great Lakes \| Maximum
Costs charged to the pipeline system and amounts payable
TransCanada and its affiliates contracts' remaining term (in years) \| Y	6
TransCanada Corporation \| Northern Border
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	$ 28.7	25.8	25.5
Impact on the Partnership's net income	13.4	12.5	12.3
Amounts payable to TransCanada and its affiliates	2.9	2.2
TransCanada Corporation \| GTN
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	22.3
Impact on the Partnership's net income	21.2
Amounts payable to TransCanada and its affiliates	3.0
TransCanada Corporation \| Bison
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	7.7
Impact on the Partnership's net income	4.3
Amounts payable to TransCanada and its affiliates	1.0
TransCanada Corporation \| North Baja Pipeline, LLC
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	3.7	4.4	2.9
Impact on the Partnership's net income	3.5	3.2	2.4
Amounts payable to TransCanada and its affiliates	0.5	0.6
TransCanada Corporation \| Tuscarora Gas Transmission Company
Costs charged to the pipeline system and amounts payable
Costs charged by TransCanada and its affiliates	4.7	3.7	3.0
Impact on the Partnership's net income	4.6	3.5	$ 2.8
Amounts payable to TransCanada and its affiliates	$ 0.6	$ 0.7

QUARTERLY FINANCIAL DATA (unaudited) (Details)
$ in Millions

3 Months Ended

12 Months Ended

Dec. 31, 2011

USD ($)

$ / shares

Sep. 30, 2011

USD ($)

$ / shares

Jun. 30, 2011

USD ($)

$ / shares

Mar. 31, 2011

USD ($)

$ / shares

Dec. 31, 2010

USD ($)

$ / shares

Sep. 30, 2010

USD ($)

$ / shares

Jun. 30, 2010

USD ($)

$ / shares

Mar. 31, 2010

USD ($)

$ / shares

Dec. 31, 2011

USD ($)

$ / shares

Dec. 31, 2010

USD ($)

$ / shares

Dec. 31, 2009

USD ($)

$ / shares

Quarterly financial data (unaudited)

$ 37.0

$ 40.4

$ 37.5

$ 38.6

$ 34.2

$ 35.6

$ 25.3

$ 30.9

$ 153.5

^[1]

$ 126.0

^[1]

$ 99.4

^[1]

17.9

17.6

17.3

17.4

17.0

17.4

70.4

69.1

67.9

Net income per common unit (in dollars per unit) | $ / shares

$ 38.3

$ 40.7

$ 36.1

$ 42.3

$ 37.1

$ 38.6

$ 27.7

$ 33.7

$ 157.4

^[1],[2]

$ 137.1

^[2]

$ 106.1

^[2],[3]

0.70

0.75

0.69

0.90

0.79

0.82

0.59

0.71

3.02

2.91

2.34

Cash distribution paid

$ 42.0

$ 35.4

$ 34.4

[1]	Includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[2]	Recast as discussed in Notes 2 and 5 and includes equity earnings from GTN and Bison from May 3, 2011, date of acquisition, to December 31, 2011.
[3]	Recast as discussed in Notes 2 and 5.

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 19
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 6
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 9

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.12)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6382870&loc=d3e33749-111570

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 11
-Article 7

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.