Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (USD $) In Millions, unless otherwise specified	Total	Preferred stock	Common stock	Capital surplus	Retained earnings	Accumulated other comprehensive income/(loss)	Shares held in RSU Trust, at cost	Treasury stock, at cost
Beginning balance at Dec. 31, 2011			$ 4,105	$ 95,602			$ (38)	$ (13,155)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of preferred stock		0
Shares issued and commitments to issue common stock for employee stock-based compensation awards, and related tax effects				(1,532)
Other				0
Dividends declared:
Purchase of treasury stock								(216)
Reissuance from treasury stock								2,170
Ending balance at Mar. 13, 2012
Beginning balance at Dec. 31, 2011			4,105		88,315	944	(38)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4,924				4,924
Dividends declared:
Preferred stock					(157)
Common stock ($0.30 per share)					(1,194)
Other comprehensive (loss)/income	1,701					1,701
Ending balance at Mar. 31, 2012	189,269	7,800	4,105	94,070	91,888	2,645	(38)	(11,201)
Beginning balance at Dec. 31, 2012		9,058	4,105	94,604	104,223	4,102	(21)	(12,002)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of preferred stock		900
Shares issued and commitments to issue common stock for employee stock-based compensation awards, and related tax effects				(1,421)
Other				(22)
Net income	6,529				6,529
Dividends declared:
Preferred stock					(175)
Common stock ($0.30 per share)					(1,175)
Other comprehensive (loss)/income	(611)					(611)
Purchase of treasury stock								(2,578)
Reissuance from treasury stock								1,570
Ending balance at Mar. 31, 2013	$ 207,086	$ 9,958	$ 4,105	$ 93,161	$ 109,402	$ 3,491	$ (21)	$ (13,010)