Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Supplemental Cash Flow Information [Abstract]
Non-cash modifications of certain mortgage loans, fixed income securities, limited partnership interests and other investments, as well as mergers completed with equity securities	$ 7	$ 12
Non-cash financing activities related to the issuance of shares for vested restricted stock units	37	68
Debt acquired	34
Net change in proceeds managed
Net change in short-term investments	(34)	27
Operating cash flow (used) provided	(34)	27
Net change in cash	0	0
Net change in proceeds managed	(34)	27
Change in Liabilities for Collateral [Roll Forward]
Liabilities for collateral, beginning of period	(840)	(782)
Liabilities for collateral, end of period	(874)	(755)
Operating cash flow provided (used)	$ 34	$ (27)