Summary of Significant Accounting Policies (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Securities loaned
Cash collateral received as percentage of fair value of securities loaned	102.00%
Deferred policy acquisition and sales inducement costs
Present value of future profits	$ 7	$ 8
Amortization expense of present value of future profits	1	2	3
Goodwill	$ 5	$ 5
Minimum
Deferred policy acquisition and sales inducement costs
Period for amortization of DAC and DSI for interest-sensitive life, fixed annuities and other investment contracts	15 years
Maximum
Securities loaned
Length of securities lending transaction period	30 days
Deferred policy acquisition and sales inducement costs
Period for amortization of DAC and DSI for interest-sensitive life, fixed annuities and other investment contracts	30 years
Interest-sensitive life insurance | Minimum
Deferred policy acquisition and sales inducement costs
Period for amortization of DAC and DSI for interest-sensitive life, fixed annuities and other investment contracts	10 years
Interest-sensitive life insurance | Maximum
Deferred policy acquisition and sales inducement costs
Period for amortization of DAC and DSI for interest-sensitive life, fixed annuities and other investment contracts	20 years
Fixed annuities | Minimum
Deferred policy acquisition and sales inducement costs
Period for amortization of DAC and DSI for interest-sensitive life, fixed annuities and other investment contracts	5 years
Fixed annuities | Maximum
Deferred policy acquisition and sales inducement costs
Period for amortization of DAC and DSI for interest-sensitive life, fixed annuities and other investment contracts	10 years