Income Taxes (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Deferred assets
Difference in tax bases of invested assets	$ 53	$ 146
Deferred reinsurance gain	27	31
Other assets	1	11
Total deferred assets	81	188
Deferred liabilities
Unrealized net capital gains	(883)	(440)
DAC	(444)	(427)
Life and annuity reserves	(193)	(56)
Other liabilities	(85)	(86)
Total deferred liabilities	(1,605)	(1,009)
Net deferred liability	(1,524)	(821)
Components of income tax expense (benefit)
Current	(82)	29	(199)
Deferred	261	196	154
Total income tax expense	179	225	(45)
Income tax refunds received	58		629
Income taxes paid		72
Current income tax receivable	$ 77	$ 53
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation
Statutory federal income tax rate - expense (as a percent)	35.00%	35.00%	(35.00%)
Tax credits (as a percent)	(3.80%)	(1.40%)	(2.20%)
Dividends received deduction (as a percent)	(1.40%)	(1.20%)	(13.10%)
State income taxes (as a percent)		0.30%	(2.10%)
Other (as a percent)	(0.20%)	(0.20%)	(0.20%)
Effective income tax rate - expense (benefit) (as a percent)	29.60%	32.50%	(52.60%)