Deferred Acquisition Costs - Deferred Policy Acquisition Costs and Asset Reconciliation (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs asset, beginning of period	$ 571	$ 546	$ 565	$ 470
Capitalized deferred policy acquisition costs	208	211	630	612
Amortized deferred policy acquisition costs	(195)	(190)	(598)	(552)
Amortized shadow deferred policy acquisition costs	6	9	(7)	46
Deferred policy acquisition costs asset, end of period	$ 590	$ 576	$ 590	$ 576