Investments (Schedule of Securities Pledged by Contractual Maturity) (Details) - USD ($) $ in Millions		6 Months Ended	12 Months Ended
		Jun. 30, 2016	Dec. 31, 2015
Repurchase Agreements		$ 689	$ 673
Securities Lending	[1]	249	242
Total gross secured borrowings		938	915
Corporate bonds [Member]
Repurchase Agreements		439	423
Securities Lending		249	242
RMBS [Member]
Repurchase Agreements		250	250
Overnight and Continuous [Member]
Securities Lending		249	242
Total gross secured borrowings		249	242
Overnight and Continuous [Member] | Corporate bonds [Member]
Securities Lending		249	242
30 to 90 Days [Member]
Repurchase Agreements		290	275
Total gross secured borrowings		290	275
30 to 90 Days [Member] | Corporate bonds [Member]
Repurchase Agreements		290	275
Greater than 90 days [Member]
Repurchase Agreements		399	398
Total gross secured borrowings		399	398
Greater than 90 days [Member] | Corporate bonds [Member]
Repurchase Agreements		149	148
Greater than 90 days [Member] | RMBS [Member]
Repurchase Agreements		$ 250	$ 250

[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.