Dispositions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Discontinued Operation, Income (Loss) from Discontinued Operation Disclosures [Abstract]
Gain (loss) on disposal, before federal income taxes		$ 1		$ (1)
Federal income tax expense (benefit)				(28)
Gain (loss) on disposal		1		27
Income (loss) from discontinued operations	$ 1	$ 1		$ 27

Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

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Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Amount of tax expense or benefit on gain (loss), not previously recognized, resulting from the sale of a business component.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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