Investments - Schedule of Selected Information about Sales of Fixed Maturities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014		Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales	$ 226,792	$ 109,024	[1]	$ 133,463	[1]
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales	226,792	109,024		133,463
Gross realized gains	259	17,583		5,948
Gross realized losses	$ (16,894)	$ (1,879)		$ (1,310)

[1] Certain balances were adjusted to give effect to discontinued operations as described in Note 1—Significant Accounting Policies.