Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Notes to Financial Statements [Abstract]
Federal income tax rate	35.00%	35.00%	35.00%	35.00%
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	$ 2,899	$ 2,807	$ 5,614	$ 5,526
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	324	304	570	617
Income (loss) from discontinued operations, after-tax	0	0	(1)	0
Net income (loss)	324	304	569	617
Annuities Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	734	735	1,465	1,468
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	158	145	294	289
Retirement Plan Services Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	258	260	510	523
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	38	41	72	90
Life Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	1,237	1,229	2,469	2,376
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	138	136	281	279
Group Protection Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	540	501	1,043	979
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	27	26	43	50
Other Operations [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	113	114	220	232
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	(39)	(22)	(73)	(60)
Excluded Realized Gain Loss Tax Reconciling Item [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	18	(33)	(95)	(53)
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	12	(21)	(61)	(34)
Benefit Ratio Unlocking Tax Reconciling Item [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	(10)	(1)	14	3
Amortization of Deferred Gains From Reserve Changes On Business Sold Through Reinsurance, Pre Tax, Reconciling Item [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	0	1	1	1
Amortization Income of DFEL Associated With Benefit Ratio Unlocking, Pre Tax, Reconciling Item [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	$ (1)	$ 0	$ 1	$ 0