Derivative Financial Instruments (Details 1) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Gross positions without netting agreements
Gross position of Other Assets	$ 4,001,000,000	$ 3,219,000,000
Gross position of Other Liabilities	(2,909,000,000)	(1,954,000,000)
Derivative Notional Values
Notional Amount of Cash Flow Hedge Instruments	1,100,000,000	1,600,000,000
Notional Amount of Fair Value Hedge Instruments	30,500,000,000	31,000,000,000
Notional Amount of Net Investment Hedge Instruments	162,600,000,000	159,500,000,000
Total Derivative Notional Values	194,200,000,000	192,100,000,000
Other Assets [Member]
Gross positions without netting agreements
Gross position of Other Assets	4,001,000,000	3,219,000,000
Impact of master netting agreements	(858,000,000)	(782,000,000)
Derivative values with impact of master netting agreements (as carried on balance sheet), assets	3,143,000,000	2,437,000,000
Cash collateral (held) pledged, Assets	(1,003,000,000)	(886,000,000)
Net position, Assets	2,140,000,000	1,551,000,000
Other Liabilities [Member]
Gross positions without netting agreements
Gross position of Other Liabilities	(2,909,000,000)	(1,954,000,000)
Impact of master netting agreements	858,000,000	782,000,000
Derivative values with impact of master netting agreements (as carried on balance sheet), Liabilities	(2,051,000,000)	(1,172,000,000)
Cash collateral (held) pledged, Liabilities	993,000,000	809,000,000
Net position, Liabilities	(1,058,000,000)	(363,000,000)
Other Contract [Member]
Derivative Notional Values
Notional Amount of Cash Flow Hedge Instruments	0	0
Notional Amount of Fair Value Hedge Instruments	0	0
Notional Amount of Net Investment Hedge Instruments	1,400,000,000	1,000,000,000
Total Derivative Notional Values	1,400,000,000	1,000,000,000
Cross currency interest rate swaps [Member]
Derivative Notional Values
Notional Amount of Cash Flow Hedge Instruments	0	0
Notional Amount of Fair Value Hedge Instruments	16,500,000,000	17,500,000,000
Notional Amount of Net Investment Hedge Instruments	300,000,000	300,000,000
Total Derivative Notional Values	16,800,000,000	17,800,000,000
Interest rate swaps [Member]
Derivative Notional Values
Notional Amount of Cash Flow Hedge Instruments	1,100,000,000	1,600,000,000
Notional Amount of Fair Value Hedge Instruments	14,000,000,000	13,500,000,000
Notional Amount of Net Investment Hedge Instruments	103,100,000,000	118,900,000,000
Total Derivative Notional Values	118,200,000,000	134,000,000,000
Floor Income contracts [Member]
Derivative Notional Values
Notional Amount of Cash Flow Hedge Instruments	0	0
Notional Amount of Fair Value Hedge Instruments	0	0
Notional Amount of Net Investment Hedge Instruments	57,800,000,000	39,300,000,000
Total Derivative Notional Values	$ 57,800,000,000	$ 39,300,000,000