Certain Long-Duration Contracts with Guarantees (Liabilities for Guarantee Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
GMDB | Variable Life, Variable Universal Life and Universal Life Contracts
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	$ 3,150	$ 2,850	$ 1,795
Incurred guarantee benefits	927	517	794
Paid guarantee benefits and other	(36)	(22)	(18)
Change in unrealized investment gains and losses	102	(193)	283
Other	0	(2)	(4)
Ending balance	4,143	3,150	2,850
GMDB | Annuity Contracts
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	714	642	461
Incurred guarantee benefits	98	167	245
Paid guarantee benefits and other	(91)	(85)	(68)
Change in unrealized investment gains and losses	0	(10)	4
Other	0	0	0
Ending balance	721	714	642
GMIB | Annuity Contracts
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	440	467	397
Incurred guarantee benefits	(18)	(40)	40
Paid guarantee benefits and other	(15)	(16)	(15)
Change in unrealized investment gains and losses	49	41	44
Other	18	(12)	1
Ending balance	474	440	467
GMAB/GMWB/GMIWB | Annuity Contracts
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	8,433	8,182	441
Incurred guarantee benefits	(194)	252	7,741
Paid guarantee benefits and other	0	0	0
Change in unrealized investment gains and losses	0	0	0
Other	(1)	(1)	0
Ending balance	$ 8,238	$ 8,433	$ 8,182