Derivative Instruments (Summary Of Credit Derivatives Sold) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Insurance Operations [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	$ 73,551	$ 112,765
Total Fair Value of Credit Derivatives	(5,343)	(5,830)
Insurance Operations [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	65,557	99,307
Total Fair Value of Credit Derivatives	(4,716)	(4,325)
Weighted average remaining maturity credit derivatives in years	5.6 Years	7.6 Years
Insurance Operations [Member] | Non-Insured Credit Default Swaps-VIE [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	643	2,612
Total Fair Value of Credit Derivatives	(527)	(1,455)
Weighted average remaining maturity credit derivatives in years	3.6 Years	4.8 Years
Insurance Operations [Member] | Insured Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	7,156	10,538
Total Fair Value of Credit Derivatives	(9)	(11)
Weighted average remaining maturity credit derivatives in years	19.7 Years	16.6 Years
Insurance Operations [Member] | All Others [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	195	308
Total Fair Value of Credit Derivatives	(91)	(39)
Weighted average remaining maturity credit derivatives in years	2.8 Years	8.5 Years
Insurance Operations [Member] | Credit Rating Below BBB [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	18,610	36,860
Total Fair Value of Credit Derivatives	(3,553)	(4,911)
Insurance Operations [Member] | Credit Rating Below BBB [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	17,639	33,377
Insurance Operations [Member] | Credit Rating Below BBB [Member] | Non-Insured Credit Default Swaps-VIE [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	643	2,612
Insurance Operations [Member] | Credit Rating Below BBB [Member] | Insured Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	133	676
Insurance Operations [Member] | Credit Rating Below BBB [Member] | All Others [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	195	195
Insurance Operations [Member] | Credit Rating BBB [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	16,631	20,096
Total Fair Value of Credit Derivatives	(1,355)	(477)
Insurance Operations [Member] | Credit Rating BBB [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	14,042	15,356
Insurance Operations [Member] | Credit Rating BBB [Member] | Insured Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	2,589	4,740
Insurance Operations [Member] | Credit Rating A [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	10,606	16,237
Total Fair Value of Credit Derivatives	(205)	(315)
Insurance Operations [Member] | Credit Rating A [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	6,336	11,323
Insurance Operations [Member] | Credit Rating A [Member] | Insured Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	4,270	4,801
Insurance Operations [Member] | Credit Rating A [Member] | All Others [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives		113
Insurance Operations [Member] | Credit Rating AA [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	12,229	18,851
Total Fair Value of Credit Derivatives	(116)	(86)
Insurance Operations [Member] | Credit Rating AA [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	12,065	18,530
Insurance Operations [Member] | Credit Rating AA [Member] | Insured Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	164	321
Insurance Operations [Member] | Credit Rating AAA [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	15,475	20,721
Total Fair Value of Credit Derivatives	(114)	(41)
Insurance Operations [Member] | Credit Rating AAA [Member] | Insured Credit Default Swaps [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	15,475	20,721
Asset/Liability Products [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	3,269	4,237
Total Fair Value of Credit Derivatives
Asset/Liability Products [Member] | Principal Protection Guarantees [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	3,269	4,237
Total Fair Value of Credit Derivatives
Weighted average remaining maturity credit derivatives in years	0.0 Years	1.0 Years
Asset/Liability Products [Member] | Credit Rating Below BBB [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Total Fair Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating Below BBB [Member] | Principal Protection Guarantees [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating BBB [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Total Fair Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating BBB [Member] | Principal Protection Guarantees [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating A [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Total Fair Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating A [Member] | Principal Protection Guarantees [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating AA [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Total Fair Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating AA [Member] | Principal Protection Guarantees [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating AAA [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	3,269	4,237
Total Fair Value of Credit Derivatives
Asset/Liability Products [Member] | Credit Rating AAA [Member] | Principal Protection Guarantees [Member]
Derivative [Line Items]
Total Notional Value of Credit Derivatives	$ 3,269	$ 4,237