Deposits - Noninterest and Interest-bearing (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
U.S. offices:
Noninterest-bearing	$ 380,320	$ 346,670
Interest-bearing
Demand	53,980	47,075
Savings	407,710	375,051
Time (included $5,140 and $3,861 at fair value)	90,416	82,738
Total interest-bearing deposits	552,106	504,864
Total deposits in U.S. offices	932,426	851,534
Non-U.S. offices:
Noninterest-bearing	17,845	18,790
Interest-bearing
Demand	195,395	188,202
Savings	1,004	687
Time (included $593 and $1,072 at fair value)	46,923	68,593
Total interest-bearing deposits	243,322	257,482
Total deposits in non-U.S. offices	261,167	276,272
Total deposits	1,193,593	1,127,806
Fair value
Interest-bearing
Time (included $5,140 and $3,861 at fair value)	5,140	3,861
Interest-bearing
Time (included $593 and $1,072 at fair value)	$ 593	$ 1,072