International Operations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Entity-Wide Information by Geographic Areas
Revenue	$ 94,205	$ 96,606	$ 97,031
Expense	64,413	70,692	68,114
Income before income tax expense	29,792	25,914	28,917
Net income	21,762	17,923	21,284
Assets	2,573,126	2,415,689	2,359,141
United Kingdom
Entity-Wide Information by Geographic Areas
Assets	434,000	451,000	498,000
Europe/Middle East and Africa
Entity-Wide Information by Geographic Areas
Revenue	16,013	15,585	10,522
Expense	10,123	9,069	9,326
Income before income tax expense	5,890	6,516	1,196
Net income	3,935	4,842	1,508
Assets	481,328	514,747	553,147
Asia and Pacific
Entity-Wide Information by Geographic Areas
Revenue	6,083	6,168	5,605
Expense	4,478	4,248	3,952
Income before income tax expense	1,605	1,920	1,653
Net income	1,051	1,254	1,048
Assets	147,357	145,999	167,955
Latin America and the Caribbean
Entity-Wide Information by Geographic Areas
Revenue	2,047	2,251	2,328
Expense	1,626	1,626	1,580
Income before income tax expense	421	625	748
Net income	269	381	454
Assets	44,567	41,473	53,984
Total international
Entity-Wide Information by Geographic Areas
Revenue	24,143	24,004	18,455
Expense	16,227	14,943	14,858
Income before income tax expense	7,916	9,061	3,597
Net income	5,255	6,477	3,010
Assets	673,252	702,219	775,086
North America
Entity-Wide Information by Geographic Areas
Revenue	70,062	72,602	78,576
Expense	48,186	55,749	53,256
Income before income tax expense	21,876	16,853	25,320
Net income	16,507	11,446	18,274
Assets	$ 1,899,874	$ 1,713,470	$ 1,584,055