International Operations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Entity-Wide Information by Geographic Areas
Total net revenue	$ 97,031	$ 97,234	$ 102,694
Expense	68,114	70,485	77,835
Income before income tax expense	28,917	26,749	24,859
Net income	21,284	18,976	17,370
Total assets	2,359,141	2,265,792	2,117,605
EMEA [Member]
Entity-Wide Information by Geographic Areas
Total net revenue	10,522	16,212	14,135
Expense	9,326	9,157	8,777
Income before income tax expense	1,196	7,055	5,358
Net income	1,508	4,844	3,635
Total assets	553,147	566,866	446,547
Asia and Pacific [Member]
Entity-Wide Information by Geographic Areas
Total net revenue	5,605	5,992	6,073
Expense	3,952	3,802	3,677
Income before income tax expense	1,653	2,190	2,396
Net income	1,048	1,380	1,614
Total assets	167,955	156,411	151,379
Latin America and the Caribbean [Member]
Entity-Wide Information by Geographic Areas
Total net revenue	2,328	2,273	1,750
Expense	1,580	1,711	1,181
Income before income tax expense	748	562	569
Net income	454	340	362
Total assets	53,984	51,481	33,192
Total International [Member]
Entity-Wide Information by Geographic Areas
Total net revenue	18,455	24,477	21,958
Expense	14,858	14,670	13,635
Income before income tax expense	3,597	9,807	8,323
Net income	3,010	6,564	5,611
Total assets	775,086	774,758	631,118
North America [Member]
Entity-Wide Information by Geographic Areas
Total net revenue	78,576	72,757	80,736
Expense	53,256	55,815	64,200
Income before income tax expense	25,320	16,942	16,536
Net income	18,274	12,412	11,759
Total assets	1,584,055	1,491,034	1,486,487
United Kingdom [Member]
Entity-Wide Information by Geographic Areas
Total assets	$ 498,000	$ 510,000	$ 419,000