NET INCOME PER SHARE - Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Basic net income per share:
Net income	$ 4,998	$ 4,825	$ 13,382	$ 7,031
Weighted average common shares outstanding (in shares)	33,032	32,398	32,884	32,336
Basic net income per common share (in dollars per share)	$ 0.15	$ 0.15	$ 0.41	$ 0.22
Diluted net income per share:
Net income	$ 4,998	$ 4,825	$ 13,382	$ 7,031
Weighted average common shares outstanding (in shares)	33,032	32,398	32,884	32,336
Effect of dilutive securities:
2016 Convertible notes (in shares)	477	0	268	0
Stock options and restricted stock (in shares)	430	406	492	460
Weighted average common shares for diluted earnings per share (in shares)	33,939	32,804	33,644	32,796
Diluted net income per common share (in dollars per share)	$ 0.15	$ 0.15	$ 0.40	$ 0.21