Supplemental Cash Flow Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental Cash Flow Information
Non-cash modifications of certain mortgage loans, fixed income securities, limited partnership interests and other investments, as well as mergers completed with equity securities	$ 120	$ 322	$ 323
Non-cash financing activities related to the issuance of shares for vested restricted stock units	47	94	39
Liabilities for collateral received reported in other liabilities and accrued expenses	780	609	784
Obligations to return cash collateral for over-the-counter ("OTC") and cleared derivatives reported in other liabilities and accrued expenses or other investments	2	15	24
Net change in proceeds managed
Net change in short-term investments	(167)	190	(341)
Operating cash flow (used) provided	(167)	190	(341)
Net change in cash	9	(6)	(5)
Net change in proceeds managed	(158)	184	(346)
Net change in liabilities
Liabilities for collateral, beginning of year	(624)	(808)	(462)
Liabilities for collateral, end of year	(782)	(624)	(808)
Operating cash flow provided (used)	$ 158	$ (184)	$ 346