Income Taxes - Schedule of Unrecognized Tax Benefits (Excluding Interest and Federal Income Tax Benefit of Unrecognized State Tax Benefits) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 326	$ 701	$ 673
Additions based on tax positions related to the current year	110	104	155
Reductions for tax positions of prior years		(100)
Reductions due to the statute of limitations		(379)	(127)
Settlements	0	0	0
Balance at end of year	$ 436	$ 326	$ 701