NET INCOME PER SHARE (Calculation of Net Income per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share [Abstract]
Net income	$ 15,089	$ 13,474	$ 44,942	$ 34,934
Basic:
Basic weighted average EPS shares	24,200	24,096	24,171	24,124
Basic net income per share	$ 0.62	$ 0.56	$ 1.86	$ 1.45
Diluted:
Basic weighted average EPS shares	24,200	24,096	24,171	24,124
Dilutive common stock equivalents	23	27	30	27
Dilutive EPS shares	24,223	24,123	24,201	24,151
Diluted net income per share	$ 0.62	$ 0.56	$ 1.86	$ 1.45
Anti-dilutive shares	5	3	3	5