Schedule of Other Than Temporary Impairments on Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
OTTI losses, gross	$ (24)	$ (31)	$ (280)
Portion of loss recognized in other comprehensive income (pre-tax)	0	0	0
Net impairment losses on fixed maturities recognized in earnings	(24)	(31)	(280)
Equity securities	(7,311)	(470)	(959)
Total	$ (7,335)	$ (501)	$ (1,239)