Income Taxes - (Benefit) Provision for Income Taxes Differs from Amounts Computed by Applying Statutory Federal Corporate Tax Rate (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
(Benefit) provision for income taxes at statutory rate	$ (2,931)	$ 281
Tax effect of:
Tax-exempt investment income	(10)	(5)
Stock-based compensation	4
State income taxes, net of federal income tax benefit and state valuation allowance	59	53
Other	9	(11)
Income tax expense (benefit)	$ (2,869)	$ 318