Consolidated Statements of Changes in Stockholders' Equity (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, 2009		$ 8,152	$ 4,105	$ 97,982	$ 62,481	$ (91)	$ (68)	$ (7,196)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock		0
Redemption of preferred stock	352	(352)
Shares issued and commitments to issue common stock for employee stock-based compensation awards, and related tax effects				706
Other				(1,273)
Cumulative effect of changes in accounting principles (Cumulative effect of a change in accounting principles)					(4,376)	(144)
Net income	17,370				17,370
Dividends declared:
Preferred stock					(642)
Common stock ($1.20, $1.00 and $0.20 per share for 2012, 2011 and 2010, respectively)					(835)
Other comprehensive income/(loss)	1,236					1,236
Reissuance from RSU Trust							15
Purchase of treasury stock								(2,999)
Reissuance from treasury stock								2,040
Share repurchases related to employee stock-based compensation awards								(5)
Ending balance at Dec. 31, 2010	176,106	7,800	4,105	97,415	73,998	1,001	(53)	(8,160)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock		0
Redemption of preferred stock	0	0
Shares issued and commitments to issue common stock for employee stock-based compensation awards, and related tax effects				(1,688)
Other				(125)
Cumulative effect of changes in accounting principles (Cumulative effect of a change in accounting principles)					0	0
Net income	18,976				18,976
Dividends declared:
Preferred stock					(629)
Common stock ($1.20, $1.00 and $0.20 per share for 2012, 2011 and 2010, respectively)					(4,030)
Other comprehensive income/(loss)	(57)					(57)
Reissuance from RSU Trust							15
Purchase of treasury stock								(8,741)
Reissuance from treasury stock								3,750
Share repurchases related to employee stock-based compensation awards								(4)
Ending balance at Dec. 31, 2011	183,573	7,800	4,105	95,602	88,315	944	(38)	(13,155)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock		1,258
Redemption of preferred stock	0	0
Shares issued and commitments to issue common stock for employee stock-based compensation awards, and related tax effects				(736)
Other				(262)
Cumulative effect of changes in accounting principles (Cumulative effect of a change in accounting principles)					0	0
Net income	21,284				21,284
Dividends declared:
Preferred stock					(647)
Common stock ($1.20, $1.00 and $0.20 per share for 2012, 2011 and 2010, respectively)					(4,729)
Other comprehensive income/(loss)	3,158					3,158
Reissuance from RSU Trust							17
Purchase of treasury stock								(1,415)
Reissuance from treasury stock								2,574
Share repurchases related to employee stock-based compensation awards								(6)
Ending balance at Dec. 31, 2012	$ 204,069	$ 9,058	$ 4,105	$ 94,604	$ 104,223	$ 4,102	$ (21)	$ (12,002)