CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Total revenue, net	$ 365,854	$ 278,834	$ 1,089,126	$ 819,634
Costs and expenses:
Cost of goods sold	143,245	101,757	425,032	287,340
Research and development	20,309	15,034	57,742	46,275
Selling, general and administrative	173,355	145,945	513,518	433,457
Intangible asset amortization	5,268	5,456	15,944	14,976
Total costs and expenses	342,177	268,192	1,012,236	782,048
Operating income	23,677	10,642	76,890	37,586
Interest income	75	89	325	160
Interest expense	(14,478)	(6,761)	(50,750)	(18,073)
Other income (expense), net	1,750	(735)	6,422	(3,691)
Income before income taxes	11,024	3,235	32,887	15,982
Income tax (benefit) expense	(2,271)	76	(2,776)	(4,406)
Net income	$ 13,295	$ 3,159	$ 35,663	$ 20,388
Net income per share
Basic (in dollars per share)	$ 0.16	$ 0.04	$ 0.43	$ 0.27
Diluted (in dollars per share)	$ 0.15	$ 0.04	$ 0.43	$ 0.26
Weighted average common shares outstanding (See Note 12):
Basic (in shares)	85,193	78,186	82,058	76,387
Diluted (in shares)	86,299	79,455	83,142	78,973
Comprehensive income (See Note 13)	$ 12,330	$ 13,534	$ 33,731	$ 53,759