CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 58	$ 49	$ 185	$ 157
Other comprehensive income
Change in fair value of cash flow hedges (Note 12)	2	(1)	(1)	(2)
Comprehensive income	60	48	184	155
Comprehensive income attributable to non-controlling interests				7
Comprehensive income attributable to controlling interests	$ 60	$ 48	$ 184	$ 148

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The consolidated profit or loss for the period including the portion attributable to the noncontrolling interest.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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