Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Supplemental Cash Flow Information [Abstract]
Non-cash modifications of certain mortgage loans, fixed income securities, limited partnerships and other investments, as well as mergers completed with equity securities	$ 63	$ 89
Liabilities Assumed	45
Net change in proceeds managed
Net change in short-term investments	6	(151)
Operating cash flow provided (used)	6	(151)
Net change in cash	1	0
Net change in proceeds managed	7	(151)
Net change in liabilities
Liabilities for collateral, beginning of period	(510)	(328)
Liabilities for collateral, end of period	(503)	(479)
Operating cash flow (used) provided	$ (7)	$ 151