Fair Value Measurements (Details - Level 3 roll forwards) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Gains (losses) included in shareholders' net income:
GMIB fair value loss	$ 224	$ 22	$ 245	$ 182
Transfers into/(out of) Level 3:
Total gains (losses) included in income attributable to instruments held at the reporting date	23	5	84	16
Changes In Level 3 Separate Account Assets [Abstract]
Beginning Balance	644	534	594	550
Policyholder gains (losses)	23	17	101	31
Purchases	111	118	226	161
Sales	(10)	(97)	(51)	(124)
Settlements	(18)	(9)	(111)	(36)
Purchases, sales, settlements	83	12	64	1
Transfers into/(out of) Level 3:
Transfers into Level 3	4	3	4	4
Transfers out of Level 3	(1)	(2)	(10)	(22)
Total transfers into/(out of) Level 3	3	1	(6)	(18)
Ending Balance	753	564	753	564
Fixed Maturities And Equity Securities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	950	945	933	845
Gains (losses) included in shareholders' net income:
GMIB fair value loss	0	0	0	0
Other	(2)	5	5	17
Total gains (losses) included in shareholders' net income	(2)	5	5	17
Gains or losses included in other comprehensive income	(1)	9	7	30
Gains or losses required to adjust future policy benefits for settlement annuities	34	30	39	91
Purchases	9	19	58	39
Sales	(1)		(1)	(1)
Settlements	(3)	(22)	(34)	(67)
Total purchases, sales, settlements	5	(3)	23	(29)
Transfers into/(out of) Level 3:
Transfers into Level 3	33	27	52	99
Transfers out of Level 3	(12)	(24)	(52)	(64)
Total transfers into/(out of) Level 3	21	3	0	35
Ending balance	1,007	989	1,007	989
Total gains (losses) included in income attributable to instruments held at the reporting date	(2)	5	4	14
Guaranteed Minimum Income Benefits Assets [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	490	658	480	482
Gains (losses) included in shareholders' net income:
GMIB fair value loss	259	24	286	211
Other	0	0	0	0
Total gains (losses) included in shareholders' net income	259	24	286	211
Gains or losses included in other comprehensive income	0	0	0	0
Gains or losses required to adjust future policy benefits for settlement annuities	0	0	0	0
Purchases	0	0	0	0
Sales	0		0	0
Settlements	(8)	(9)	(25)	(20)
Total purchases, sales, settlements	(8)	(9)	(25)	(20)
Transfers into/(out of) Level 3:
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Total transfers into/(out of) Level 3	0	0	0	0
Ending balance	741	673	741	673
Total gains (losses) included in income attributable to instruments held at the reporting date	259	24	286	211
Guaranteed Minimum Income Benefits Liabilities [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	(917)	(1,221)	(903)	(903)
Gains (losses) included in shareholders' net income:
GMIB fair value loss	(483)	(46)	(531)	(393)
Other	0	0	0	0
Total gains (losses) included in shareholders' net income	(483)	(46)	(531)	(393)
Gains or losses included in other comprehensive income	0	0	0	0
Gains or losses required to adjust future policy benefits for settlement annuities	0	0	0	0
Purchases	0	0	0	0
Sales	0		0	0
Settlements	16	21	50	50
Total purchases, sales, settlements	16	21	50	50
Transfers into/(out of) Level 3:
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Total transfers into/(out of) Level 3	0	0	0	0
Ending balance	(1,384)	(1,246)	(1,384)	(1,246)
Total gains (losses) included in income attributable to instruments held at the reporting date	(483)	(46)	(531)	(393)
Guaranteed Minimum Income Benefits Net [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	(427)	(563)	(423)	(421)
Gains (losses) included in shareholders' net income:
GMIB fair value loss	(224)	(22)	(245)	(182)
Other	0	0	0	0
Total gains (losses) included in shareholders' net income	(224)	(22)	(245)	(182)
Gains or losses included in other comprehensive income	0	0	0	0
Gains or losses required to adjust future policy benefits for settlement annuities	0	0	0	0
Purchases	0	0	0	0
Sales	0		0	0
Settlements	8	12	25	30
Total purchases, sales, settlements	8	12	25	30
Transfers into/(out of) Level 3:
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Total transfers into/(out of) Level 3	0	0	0	0
Ending balance	(643)	(573)	(643)	(573)
Total gains (losses) included in income attributable to instruments held at the reporting date	$ (224)	$ (22)	$ (245)	$ (182)

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Purchases that have taken place during the period in relation to assets and liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).

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Sales that have taken place during the period in relation to assets and liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Settlements that have taken place during the period in relation to assets and liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents total gains or losses for the period (realized and unrealized), arising from assets and liabilities included in income attributable to instruments held at the reporting date, measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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This element represents total gains or losses for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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This element represents transfers into assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents [net] transfers in to and out of assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents transfers out of assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents total unrealized gains or losses for the period arising from assets or liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

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This element represents total gains or losses for the period (realized and unrealized), arising from assets or liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in gains or losses required to adjust future policy benefits for settlement annuities.

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This element represents an asset or liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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This element represents other gains or losses for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) other than GMIB, which are included in earnings or resulted in a change in net asset value.

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This element represents policyholder gains (losses) which have taken place during the period in relation to separate account assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

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This element represents purchases, which have taken place during the period in relation to separate account assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

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Net purchases, sales and settlements of separate account assets classified as level 3 using significant unobservable inputs in the fair value calculation

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Sales of separate account assets classified as leve 3 with signficant unobservable inputs to the fair value calculation

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Settlements of separate account assets classified as level 3 with significant unobservable inputs to the fair value calculation

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This element represents [net] transfers into and out of separate account assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents transfers out of separate account assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents transfers into separate account assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents a separate account asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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The amount of the change in fair value of the net GMIB liability less cash settled in the period for reinsurance on Guaranteed Minimum Income Benefit contracts.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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