CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Total revenue, net	$ 244,078	$ 231,351	$ 477,743	$ 446,410
Costs and expenses:
Cost of goods sold	86,539	86,976	173,261	169,359
Research and development	13,891	13,745	26,447	26,312
Selling, general and administrative	126,590	115,253	240,654	223,591
Intangible asset amortization	3,104	2,985	6,639	6,018
Total costs and expenses	230,124	218,959	447,001	425,280
Operating income	13,954	12,392	30,742	21,130
Interest income	8	58	13	120
Interest expense	(5,471)	(5,382)	(10,963)	(10,524)
Other (expense) income, net	(919)	118	397	435
Income before income taxes	7,572	7,186	20,189	11,161
Income tax expense	2,574	2,361	6,807	4,130
Net income	$ 4,998	$ 4,825	$ 13,382	$ 7,031
Basic net income per common share (in dollars per share)	$ 0.15	$ 0.15	$ 0.41	$ 0.22
Diluted net income per common share (in dollars per share)	$ 0.15	$ 0.15	$ 0.40	$ 0.21
Weighted average common shares outstanding (See Note 10):
Basic (in shares)	33,032	32,398	32,884	32,336
Diluted (in shares)	33,939	32,804	33,644	32,796
Comprehensive income (loss) (See Note 11)	$ 12,325	$ 4,752	$ (3,418)	$ 7,957