Derivative Financial Instruments (Details 7) (Cash Flow Hedges [Member], USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Derivatives in cash flow hedging relationships Abstract
Amount of Gains (Losses) Deferred in Accumulated Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	$ 1,630	$ (40)	$ 1,527	$ 577
Interest rate swaps [Member]
Derivatives in cash flow hedging relationships Abstract
Amount of Gains (Losses) Deferred in Accumulated Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	927	181	944	457
Interest rate swaps [Member] | Net Investment Income [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	0	0	1	0
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Interest rate swaps [Member] | Other Expenses [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(3)	0	(7)	0
Interest rate swaps [Member] | Net Derivative Gain (Losses) [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(42)	0	(41)	0
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	(1)	1	1	3
Interest rate forwards [Member]
Derivatives in cash flow hedging relationships Abstract
Amount of Gains (Losses) Deferred in Accumulated Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	289	15	307	0
Interest rate forwards [Member] | Net Investment Income [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	0	1	1	2
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Interest rate forwards [Member] | Other Expenses [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	0	0	(1)	0
Interest rate forwards [Member] | Net Derivative Gain (Losses) [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(1)	0	21	11
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	27	0	16	0
Foreign currency swaps [Member]
Derivatives in cash flow hedging relationships Abstract
Amount of Gains (Losses) Deferred in Accumulated Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	399	(247)	259	92
Foreign currency swaps [Member] | Net Investment Income [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(2)	(2)	(5)	(5)
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Foreign currency swaps [Member] | Other Expenses [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	0	0	1	1
Foreign currency swaps [Member] | Net Derivative Gain (Losses) [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	25	1	10	(61)
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	5	(3)	3	0
Credit forwards [Member]
Derivatives in cash flow hedging relationships Abstract
Amount of Gains (Losses) Deferred in Accumulated Other Comprehensive Income (Loss) on Derivatives (Effective Portion)	15	11	17	28
Credit forwards [Member] | Net Investment Income [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	1	0	1	0
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Credit forwards [Member] | Other Expenses [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	0	0	0	0
Credit forwards [Member] | Net Derivative Gain (Losses) [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	1	0	1	0
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Net Investment Income [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(1)	(1)	(2)	(3)
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	0	0
Other Expenses [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(3)	0	(7)	1
Net Derivative Gain (Losses) [Member]
Derivatives in cash flow hedging relationships Abstract
Amount and Location of Gains (Losses) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (Loss) (Effective Portion)	(17)	1	(9)	(50)
Amount and Location of Gains (Losses) Recognized In Income on Derivatives (Ineffective Portion and Amount Excluded from Effectiveness Testing)	$ 31	$ (2)	$ 20	$ 3