Related Party (Affiliated Asset Transfers) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2013	Sep. 30, 2013	Dec. 31, 2014
Related Party Transactions [Line Items]
Fixed maturity asset transfer amortized cost			$ 36
Fixed maturity asset transfer fair value			44
Realized gain on fixed maturity asset transfer			8
Commercial mortgage loans asset transfer amortized cost	90	6	6
Commercial mortgage loans asset transfer fair value	103	6	6
Realized gain on commerical mortgage loan asset transfer	8	1
Fixed maturity asset purchase amortized cost			27
Fixed maturity asset purchase fair value			$ 30