Fair Value of Assets and Liabilities (Details 6) (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Financial assets
Mortgage loans	$ 3,770	$ 3,686
Financial liabilities
Notes due to related parties	275	275
Liability for collateral	465	510	$ 610	$ 328
Carrying value
Financial assets
Cost method limited partnerships	510	508
Bank loans	478	431
Agent loans	404	368
Notes due from related party	275	275
Financial liabilities
Contractholder funds on investment contracts	13,082	13,708
Notes due to related parties	275	275
Liability for collateral	465	510
Fair value
Financial assets
Mortgage loans	4,023	3,922
Cost method limited partnerships	675	686
Bank loans	476	427
Agent loans	393	361
Notes due from related party	275	275
Financial liabilities
Contractholder funds on investment contracts	13,644	14,364
Notes due to related parties	275	275
Liability for collateral	$ 465	$ 510