CONSOLIDATED STATEMENTS OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONSOLIDATED STATEMENTS OF INCOME
Transmission revenues	$ 87us-gaap_GasDomesticRegulatedRevenue	$ 87us-gaap_GasDomesticRegulatedRevenue
Equity earnings from unconsolidated affiliates (Note 4)	31	33
Operation and maintenance expenses	(11)us-gaap_OperatingCostsAndExpenses	(12)us-gaap_OperatingCostsAndExpenses
Property taxes	(6)us-gaap_RealEstateTaxExpense	(6)us-gaap_RealEstateTaxExpense
General and administrative	(3)us-gaap_GeneralAndAdministrativeExpense	(2)us-gaap_GeneralAndAdministrativeExpense
Depreciation	(21)us-gaap_Depreciation	(21)us-gaap_Depreciation
Financial charges and other	(13)	(12)
Net income	64us-gaap_ProfitLoss	67us-gaap_ProfitLoss
Net income attributable to non-controlling interests	7	10
Net income attributable to controlling interests	57us-gaap_NetIncomeLoss	57us-gaap_NetIncomeLoss
Net income attributable to controlling interests allocation (Note 7)
Common units	56	56
General Partner	1	1
Net income allocated to partners	$ 57us-gaap_IncomeLossAttributableToParent	$ 57us-gaap_IncomeLossAttributableToParent
Net income per common unit (Note 7) - basic (in dollars per unit)	$ 0.88	$ 0.90
Net income per common unit (Note 7) - diluted (in dollars per unit)	$ 0.88	$ 0.90
Weighted average common units outstanding (millions) - basic (in units)	63.6	62.3
Weighted average common units outstanding (millions) - diluted (in units)	63.6	62.3
Common units outstanding, end of period (millions) (in units)	63.6	62.3

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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