Investments (Schedule of Securities Pledged by Contractual Maturity) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Repurchase Agreements		$ 535	$ 673
Securities Lending	[1]	216	242
Total gross secured borrowings		751	915
Corporate bonds [Member]
Repurchase Agreements		535	423
Securities Lending		212	242
RMBS [Member]
Repurchase Agreements			250
Foreign government bonds [Member]
Securities Lending		4
Overnight and Continuous [Member]
Securities Lending		216	242
Total gross secured borrowings		216	242
Overnight and Continuous [Member] | Corporate bonds [Member]
Securities Lending		212	242
Overnight and Continuous [Member] | Foreign government bonds [Member]
Securities Lending		4
30 to 90 Days [Member]
Repurchase Agreements		389	275
Total gross secured borrowings		389	275
30 to 90 Days [Member] | Corporate bonds [Member]
Repurchase Agreements		389	275
Greater than 90 days [Member]
Repurchase Agreements		146	398
Total gross secured borrowings		146	398
Greater than 90 days [Member] | Corporate bonds [Member]
Repurchase Agreements		$ 146	148
Greater than 90 days [Member] | RMBS [Member]
Repurchase Agreements			$ 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.