Fair Value Disclosures (Assets Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Assets
Loans	$ 69,010		$ 69,010		$ 57,119
Other investments	4,282		4,282		4,355
Premises, equipment and software costs	6,259		6,259		6,108
Intangible assets	3,069		3,069		3,159
Goodwill	6,587		6,587		6,588
Other assets	9,160		9,160		10,742
Liabilities
Other liabilities and accrued expenses	(19,129)		(19,129)		(19,441)
Total liabilities	(757,693)		(757,693)		(729,406)
Fair Value
Loans	11,334		11,334		11,962
Other investments	64,687		64,687		69,316
Intangible assets	5		5		$ 6
Global Oil Merchanting Business
Additional Disclosures
Impairment charges recognized in Other revenues	10		69
Nonrecurring
Assets
Loans	5,089	$ 2,672	5,089	$ 2,672
Other investments	0	38	0	38
Premises, equipment and software costs	0	0	0	0
Intangible assets		20		20
Other assets		0		0
Total carrying value	5,089	2,730	5,089	2,730
Liabilities
Other liabilities and accrued expenses	(427)		(427)
Total liabilities	(427)		(427)
Nonrecurring | Other Assets
Fair Value
Gains (losses) in fair value adjustment - Assets		0		(9)
Nonrecurring | Loans
Fair Value
Gains (losses) in fair value adjustment - Assets	12	(45)	(201)	(55)
Nonrecurring | Other Investments
Fair Value
Gains (losses) in fair value adjustment - Assets	0	(2)	(2)	(27)
Nonrecurring | Premises, Equipment and Software Costs
Fair Value
Gains (losses) in fair value adjustment - Assets	(2)	(27)	(24)	(43)
Nonrecurring | Intangible Assets
Fair Value
Gains (losses) in fair value adjustment - Assets		(4)		(6)
Nonrecurring | Total assets
Fair Value
Gains (losses) in fair value adjustment - Assets	10	(78)	(227)	(140)
Nonrecurring | Other Liabilities and accrued expenses
Fair Value
Gains (losses) in fair value adjustment - Liabilities	(144)		(171)
Nonrecurring | Total liabilities
Fair Value
Gains (losses) in fair value adjustment - Liabilities	(144)		(171)
Nonrecurring | Level 1
Fair Value
Loans	0	0	0	0
Other investments	0	0	0	0
Premises, equipment and software costs	0	0	0	0
Intangible assets		0		0
Other assets		0		0
Total assets measured at fair value	0	0	0	0
Other liabilities and accrued expenses	0		0
Total Liabilities, Fair value	0		0
Nonrecurring | Level 2
Fair Value
Loans	3,060	1,996	3,060	1,996
Other investments	0	0	0	0
Premises, equipment and software costs	0	0	0	0
Intangible assets		0		0
Other assets		0		0
Total assets measured at fair value	3,060	1,996	3,060	1,996
Other liabilities and accrued expenses	(365)		(365)
Total Liabilities, Fair value	(365)		(365)
Nonrecurring | Level 3
Fair Value
Loans	2,029	676	2,029	676
Other investments	0	38	0	38
Premises, equipment and software costs	0	0	0	0
Intangible assets		20		20
Other assets		0		0
Total assets measured at fair value	2,029	$ 734	2,029	$ 734
Other liabilities and accrued expenses	(62)		(62)
Total Liabilities, Fair value	$ (62)		$ (62)