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			9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013		Sep. 30, 2014	Sep. 30, 2013
Basic net income per share:
Net income (loss)	$ 9,807	$ (30,330)	[1]	$ 16,838	$ (34,838)	[1]
Weighted average common shares outstanding (in shares)	32,450	27,896	[1]	32,374	27,855	[1]
Basic net income per common share (in dollars per share)	$ 0.30	$ (1.09)	[1]	$ 0.52	$ (1.25)	[1]
Diluted net income per share:
Net income (loss)	$ 9,807	$ (30,330)	[1]	$ 16,838	$ (34,838)	[1]
Weighted average common shares outstanding (in shares)	32,450	27,896	[1]	32,374	27,855	[1]
Effect of dilutive securities:
Stock options and restricted stock (in shares)	456	0		470	0
Weighted average common shares for diluted earnings per share (in shares)	32,906	27,896	[1]	32,844	27,855	[1]
Diluted net income per common share (in dollars per share)	$ 0.30	$ (1.09)	[1]	$ 0.51	$ (1.25)	[1]

[1] See Note 1 of these condensed consolidated financial statements for discussion of the impact of the change in accounting for the medical device excise tax.