Investments (Schedule of Securities Pledged by Contractual Maturity) (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2016	Dec. 31, 2015
Repurchase Agreements		$ 502	$ 673
Securities Lending	[1]	246	242
Total secured borrowings		748	915
Gross amount of recognized liabilities for repurchase		$ 748	914
Amounts related to agreements not included in offsetting
RMBS [Member]
Repurchase Agreements		$ 250	250
Corporate bonds [Member]
Repurchase Agreements		252	423
Securities Lending		246	242
Overnight and Continuous [Member]
Securities Lending		246	242
Total secured borrowings		246	242
Overnight and Continuous [Member] | Corporate bonds [Member]
Securities Lending		246	242
30 to 90 Days [Member]
Repurchase Agreements		100	275
Total secured borrowings		100	275
30 to 90 Days [Member] | Corporate bonds [Member]
Repurchase Agreements		100	275
Greater than 90 days [Member]
Repurchase Agreements		402	398
Total secured borrowings		402	398
Greater than 90 days [Member] | RMBS [Member]
Repurchase Agreements		250	250
Greater than 90 days [Member] | Corporate bonds [Member]
Repurchase Agreements		$ 152	$ 148

[1] Our pledged securities under securities lending agreements are included in fixed maturity AFS securities on our Consolidated Balance Sheets. We generally obtain collateral in an amount equal to 102% and 105% of the fair value of the domestic and foreign securities, respectively. We value collateral daily and obtain additional collateral when deemed appropriate. The cash received in our securities lending program is typically invested in cash and invested cash or fixed maturity AFS securities.