Derivative Financial Instruments and Off-balance sheet Financial Instruments (Details 4) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Derivative Financial Instruments and Off-balance sheet Financial Instruments
Cash flow hedge gain to be reclassified from AOCI during the next twelve months	$ 3
Net gain (loss) recognized in earnings during the reporting period representing the amount of the fair value of the hedges' ineffectiveness.	0	$ 0	$ 0
Effective portion
Gain recognized in OCI on derivatives during the period	10	12	3
Gain (loss) recognized in OCI on derivatives during the term of the hedging relationship	6	(2)	(18)
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(18)	(2)	115
Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(24)	(36)	(10)
Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(7)	15	74
Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	22	22	16
Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(9)	1	41
Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	(4)	(6)
Interest rate contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	1	(14)	(2)
Interest rate contracts | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	1	(10)	4
Interest rate contracts | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Interest rate contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Interest rate contracts | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Interest rate contracts | Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	(4)	(6)
Equity and index contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(9)	29	116
Equity and index contracts | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	1	(18)	(12)
Equity and index contracts | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Equity and index contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(9)	38	94
Equity and index contracts | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(1)	9	34
Equity and index contracts | Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Embedded derivative financial instruments
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	24	1	(2)
Embedded derivative financial instruments | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	(1)
Embedded derivative financial instruments | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(7)	15	74
Embedded derivative financial instruments | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	31	(14)	(75)
Embedded derivative financial instruments | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Embedded derivative financial instruments | Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Foreign currency contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(32)	(17)	(2)
Foreign currency contracts | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(24)	(9)	(9)
Foreign currency contracts | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Foreign currency contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Foreign currency contracts | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(8)	(8)	7
Foreign currency contracts | Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Credit default swaps
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(2)	1	8
Credit default swaps | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	(2)	1	8
Credit default swaps | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Credit default swaps | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Credit default swaps | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Credit default swaps | Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Other contracts
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	(2)	(3)
Other contracts | Realized capital gains and losses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Other contracts | Life and annuity contract benefits
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Other contracts | Interest credited to contractholder funds
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	(2)	(3)
Other contracts | Operating costs and expenses
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	0	0	0
Other contracts | Loss on disposition of operations
Derivative Instruments, Gain (Loss)
Derivatives not designated as accounting hedging instruments, total gain (loss) recognized in net income on derivatives	$ 0	$ 0	$ 0