Closed Block (Closed Block Revenues and Benefits and Expenses) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues
Premiums	$ 701	$ 711	$ 1,335	$ 1,350
Net investment income	642	683	1,351	1,404
Realized investment gains (losses), net	166	369	539	504
Other income	18	19	21	34
Total Closed Block revenues	1,527	1,782	3,246	3,292
Benefits and Expenses
Policyholders’ benefits	895	911	1,716	1,703
Interest credited to policyholders’ account balances	34	33	67	67
Dividends to policyholders	423	688	1,187	1,265
General and administrative expenses	107	111	215	225
Total Closed Block benefits and expenses	1,459	1,743	3,185	3,260
Closed Block revenues, net of Closed Block benefits and expenses, before income taxes and discontinued operations	68	39	61	32
Income tax expense (benefit)	57	33	39	21
Closed Block revenues, net of Closed Block benefits and expenses and income taxes, before discontinued operations	11	6	22	11
Income (loss) from discontinued operations, net of taxes	0	0	0	0
Closed Block revenues, net of Closed Block benefits and expenses, income taxes and discontinued operations	$ 11	$ 6	$ 22	$ 11