Consolidated Statements of Changes in Equity (Deficit) (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Stockholders' Equity [Abstract]
Tax on unrealized losses on available-for-sale securities	$ 702	$ 250	$ 1,644
Tax on reclassification adjustment for other-than-temporary impairments recognized in net income (loss)	250	99	253
Tax on reclassification adjustment for (gains) losses included in net income (loss)	$ 9	$ 28	$ 10