CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (UNAUDITED) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013		Jun. 30, 2014	Jun. 30, 2013
Income Statement [Abstract]
Total revenue, net	$ 231,351	$ 205,547	[1]	$ 446,410	$ 402,199	[1]
Costs and Expenses:
Cost of goods sold	86,976	81,829	[1]	169,359	161,441	[1]
Research and development	13,745	11,809	[1]	26,312	24,525	[1]
Selling, general and administrative	115,253	103,280	[1]	223,591	206,243	[1]
Intangible asset amortization	2,985	3,073	[1]	6,018	6,624	[1]
Total costs and expenses	218,959	199,991	[1]	425,280	398,833	[1]
Operating income	12,392	5,556	[1]	21,130	3,366	[1]
Interest income	58	289	[1]	120	352	[1]
Interest expense	(5,382)	(4,965)	[1]	(10,524)	(9,765)	[1]
Other income (expense), net	118	(307)	[1]	435	(1,281)	[1]
Income (loss) before income taxes	7,186	573	[1]	11,161	(7,328)	[1]
Income tax expense (benefit)	2,361	(947)	[1]	4,130	(2,820)	[1]
Net income (loss)	4,825	1,520	[1]	7,031	(4,508)	[1]
Basic net income per common share (in dollars per share)	$ 0.15	$ 0.05	[1]	$ 0.22	$ (0.16)	[1]
Diluted net income per common share (in dollars per share)	$ 0.15	$ 0.05	[1]	$ 0.21	$ (0.16)	[1]
Weighted average common shares outstanding (See Note 10):
Basic (in shares)	32,398	27,873	[1]	32,336	27,834	[1]
Diluted (in shares)	32,804	28,118	[1]	32,796	27,834	[1]
Comprehensive income (loss) (See Note 11)	$ 4,752	$ 3,397	[1]	$ 7,957	$ (9,115)	[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.