Consolidated Statement Of Changes In Equity (USD $) In Millions	Total	Common stock and paid-in capital [Member]	Mandatorily convertible preferred stock held by U.S. Department Of Treasury [Member]	Preferred stock [Member]	Retained earnings (accumulated deficit) [Member]	Accumulated Other Comprehensive Income [Member]
Beginning Balance at Dec. 31, 2011	$ 19,280	$ 19,668	$ 5,685	$ 1,255	$ (7,415)	$ 87
Net income (loss)	310				310
Preferred stock dividends - U.S. Department of Treasury	(134)				(134)
Preferred stock dividends	(67)				(67)
Other comprehensive income (loss)	187					187
Ending Balance at Mar. 31, 2012	19,576	19,668	5,685	1,255	(7,306)	274
Beginning Balance at Dec. 31, 2012	19,898	19,668	5,685	1,255	(7,021)	311
Net income (loss)	1,093				1,093
Preferred stock dividends - U.S. Department of Treasury	(133)				(133)
Preferred stock dividends	(67)				(67)
Other comprehensive income (loss)	(317)					(317)
Ending Balance at Mar. 31, 2013	$ 20,474	$ 19,668	$ 5,685	$ 1,255	$ (6,128)	$ (6)