Derivatives and Hedging Activities (Details 1) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Fair value hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) on Derivatives	$ 82	$ 195
Net Gains (Losses) on Hedged Item	3	(95)
Cash flow hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Recognized in OCI (Effective Portion)	37	33
Net Gains (Losses) Reclassified From OCI Into Income (Effective Portion)	24	22
Net Gains (Losses) Recognized in Income (Ineffective Portion)
Foreign exchange [Member] | Net Investment Hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Recognized in OCI (Effective Portion)	(6)
Other Income [Member] | Cash flow hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Recognized in Income (Ineffective Portion)
Other Income [Member] | Interest rate [Member] | Fair value hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) on Derivatives	(13)	(12)
Net Gains (Losses) on Hedged Item	10	8
Other Income [Member] | Foreign exchange [Member] | Fair value hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) on Derivatives	5	90
Net Gains (Losses) on Hedged Item	(6)	(95)
Other Income [Member] | Foreign exchange [Member] | Net Investment Hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Recognized in Income (Ineffective Portion)
Interest Expense [Member] | Cash flow hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Reclassified From OCI Into Income (Effective Portion)	(5)	(5)
Interest Expense [Member] | Interest rate [Member] | Fair value hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) on Derivatives	89	112
Interest Expense [Member] | Interest rate [Member] | Cash flow hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Recognized in OCI (Effective Portion)	(7)	(9)
Interest Expense [Member] | Foreign exchange [Member] | Fair value hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) on Derivatives	1	5
Net Gains (Losses) on Hedged Item	(1)	(8)
Interest Income [Member] | Cash flow hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Reclassified From OCI Into Income (Effective Portion)	29	27
Interest Income [Member] | Interest rate [Member] | Cash flow hedges [Member]
Pre-tax net gains (losses) on fair value hedges
Net Gains (Losses) Recognized in OCI (Effective Portion)	$ 50	$ 42