Activity Impacting Deferred Acquisition Costs (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred Policy Acquisition Costs [Line Items]
Unamortized beginning balance	$ 5,200	$ 5,214	$ 5,220
Impact of foreign currency translation	(23)	(15)	(16)
Costs deferred	295	385	365
Amortization, net of interest accretion	(448)	(384)	(355)
Impairment	(455)	0	0
Unamortized ending balance	4,569	5,200	5,214
Accumulated effect of net unrealized investment (gains) losses	(171)	(348)	(176)
Ending balance	$ 4,398	$ 4,852	$ 5,038