Reinsurance - Guaranteed Minimum Death Benefit Contracts, Future Policy Benefits (Details) - Variable Annuity [Member] - Guaranteed Minimum Death Benefit [Member] - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Activity in future policy benefits reserves for GMDB business [Line Items]
Future Policy Benefit Reserve, beginning balance, gross	$ 1,252	$ 1,270
Costs payable, beginning balance, gross	18	16
Less: Reinsurance and other amounts recoverable	1,164	1,186
Balance at January 1, net	106	100
Add: Incurred benefits	4	3
Less: Paid benefits	(1)	(3)
Ending balance, net	111	106
Costs payable, ending balance, gross	18	18
Add: Reinsurance and other amounts recoverable	1,132	1,164
Future Policy Benefit Reserve, ending balance, gross	$ 1,225	$ 1,252