Stock Compensation - Summary of Activity in Plans (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares, Outstanding at beginning of year	572,323
Shares, Exercised	(165,405)
Shares, Forfeited and expired	(1,200)
Shares, Outstanding at end of period	405,718
Shares, Options exercisable at end of period	397,419
Weighted average exercise price, Outstanding at beginning of year	$ 2.56
Weighted average exercise price, Exercised	2.80
Weighted average exercise price, Forfeited and expired	2.10
Weighted average exercise price, Outstanding at end of period	2.47
Weighted average exercise price, Options exercisable at the end of period	$ 2.41
Aggregate intrinsic value, Outstanding at end of period	$ 1,876
Aggregate intrinsic value, Options exercisable at the end of period	$ 1,868