Closed Block (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues
Premiums	$ 2,139	$ 2,306	$ 2,461
Net investment income	2,188	2,231	2,292
Net investment gains (losses)	61	32	39
Net derivative gains (losses)	(12)	8	(27)
Total revenues	4,376	4,577	4,765
Expenses
Policyholder benefits and claims	2,783	2,991	3,115
Policyholder dividends	1,072	1,137	1,235
Other expenses	179	193	199
Total expenses	4,034	4,321	4,549
Revenues, net of expenses before provision for income tax expense (benefit)	342	256	216
Provision for income tax expense (benefit)	120	89	71
Revenues, net of expenses and provision for income tax expense (benefit) from continuing operations	222	167	145
Revenues, net of expenses and provision for income tax expense (benefit) from discontinued operations	10	1	1
Revenues, net of expenses and provision for income tax expense (benefit)	$ 232	$ 168	$ 146