Derivative Instruments - Impact on Statements of Income, Fair Value Hedges (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Gains/(losses) recorded in income
Derivatives	$ (3,417)	$ (371)	$ 3,986	$ 154
Hedged items	3,511	698	(3,504)	477
Total income statement impact	94	327	482	631
Income statement impact due to:
Hedge ineffectiveness	(24)	56	(13)	100
Excluded components	118	271	495	531
Interest rate contracts
Gains/(losses) recorded in income
Derivatives	(1,541)	578	(935)	1,321
Hedged items	1,709	(261)	1,461	(668)
Total income statement impact	168	317	526	653
Income statement impact due to:
Hedge ineffectiveness	(19)	43	(2)	72
Excluded components	187	274	528	581
Foreign exchange contracts
Gains/(losses) recorded in income
Derivatives	(2,118)	(388)	4,357	(786)
Hedged items	2,097	307	(4,362)	631
Total income statement impact	(21)	(81)	(5)	(155)
Income statement impact due to:
Hedge ineffectiveness	0	0	0	0
Excluded components	(21)	(81)	(5)	(155)
Commodity contracts
Gains/(losses) recorded in income
Derivatives	242	(561)	564	(381)
Hedged items	(295)	652	(603)	514
Total income statement impact	(53)	91	(39)	133
Income statement impact due to:
Hedge ineffectiveness	(5)	13	(11)	28
Excluded components	$ (48)	$ 78	$ (28)	$ 105