Fair Value of Assets and Liabilities (Details 6) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Financial assets
Mortgage loans	$ 3,827	$ 3,686
Financial liabilities
Notes due to related parties	275	275
Liability for collateral	503	510	$ 479	$ 328
Carrying value
Financial assets
Cost method limited partnerships	526	508
Bank loans	510	431
Agent loans	416	368
Notes due from related party	275	275
Financial liabilities
Contractholder funds on investment contracts	12,682	13,708
Notes due to related parties	275	275
Liability for collateral	503	510
Fair value
Financial assets
Mortgage loans	4,020	3,922
Cost method limited partnerships	692	686
Bank loans	507	427
Agent loans	406	361
Notes due from related party	275	275
Financial liabilities
Contractholder funds on investment contracts	13,189	14,364
Notes due to related parties	275	275
Liability for collateral	$ 503	$ 510