Consolidated Statements of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net Income (loss)	$ 242us-gaap_NetIncomeLoss	$ (212)us-gaap_NetIncomeLoss	$ 285us-gaap_NetIncomeLoss
Other Comprehensive Income (Loss) from Continuing Operations
Losses on treasury rate locks reclassified into income	1	1
Pension and other postretirement benefit plans	(20)	13	(14)
Other comprehensive (loss) income, before income taxes	(19)	14	(14)
Income tax (benefit) expense related to other comprehensive income	(7)us-gaap_OtherComprehensiveIncomeLossTax	6us-gaap_OtherComprehensiveIncomeLossTax	(6)us-gaap_OtherComprehensiveIncomeLossTax
Other comprehensive (loss) income from continuing operations, net of income taxes	(12)	8	(8)
Other Comprehensive Income from Discontinued Operations, Net of Income Taxes		6	23
Comprehensive Income (Loss)	$ 230us-gaap_ComprehensiveIncomeNetOfTax	$ (198)us-gaap_ComprehensiveIncomeNetOfTax	$ 300us-gaap_ComprehensiveIncomeNetOfTax

Net changes to accumulated comprehensive income during the period related to discontinued operations, after tax.

No definition available.

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The amount of expense charged against earnings by an Entity to record deferred gains and losses on hedge instruments. Examples include gain on economic hedges, amortization of gain on designated fair value hedge and so forth.

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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, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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