Consolidated Statements of Operations (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Income from operations of discontinued businesses, income tax expense (benefit)	$ 23	$ 24	$ 26
Gain (loss) from disposal and impairment of discontinued businesses, income tax expense (benefit)	$ 4	$ (15)	$ 68

Income tax expense or benefit attributable to Income or Loss from discontinued operations during the phase-out period.

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

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