Deferred Acquisition Costs - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Deferred Policy Acquisition Costs [Line Items]
Deferred Policy acquistion costs amortization			$ 257	$ 266
DAC impairment related to life block transaction			$ 0	455
Loss Recognition Testing | Immediate Fixed Annuity
Deferred Policy Acquisition Costs [Line Items]
Deferred Policy acquistion costs amortization		$ 14
Increase in future policy benefit reserves	$ 6	$ 18
Life Block Transaction | Loss Recognition Testing | Term Life Insurance
Deferred Policy Acquisition Costs [Line Items]
DAC impairment related to life block transaction				$ 455