NET INCOME PER SHARE - Basic and Diluted Net Income Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Basic net income per share:
Net income	$ 8,384	$ 2,206
Weighted average common shares outstanding (in shares)	32,736	32,275
Basic net income per common share (in dollars per share)	$ 0.26	$ 0.07
Diluted net income per share:
Net income	$ 8,384	$ 2,206
Weighted average common shares outstanding (in shares)	32,736	32,275
Effect of dilutive securities:
2016 Convertible notes (in shares)	30	0
Stock options and restricted stock (in shares)	576	493
Weighted average common shares for diluted earnings per share (in shares)	33,342	32,768
Diluted net income per common share (in dollars per share)	$ 0.25	$ 0.07