CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Total revenue, net	$ 366,190	$ 282,164	$ 723,272	$ 540,801
Costs and expenses:
Cost of goods sold	137,565	98,998	281,787	185,583
Research and development	19,108	15,747	37,433	31,241
Selling, general and administrative	176,597	145,015	340,163	287,512
Intangible asset amortization	5,286	5,419	10,676	9,520
Total costs and expenses	338,556	265,179	670,059	513,856
Operating income	27,634	16,985	53,213	26,945
Interest income	174	64	250	71
Interest expense	(17,504)	(6,181)	(36,272)	(11,312)
Other income (expense), net	2,427	(2,866)	4,672	(2,956)
Income before income taxes	12,731	8,002	21,863	12,748
Income tax expense (benefit)	1,355	(2,833)	(505)	(4,482)
Net income	$ 11,376	$ 10,835	$ 22,368	$ 17,230
Net income per share
Basic (in dollars per share)	$ 0.14	$ 0.14	$ 0.28	$ 0.23
Diluted (in dollars per share)	$ 0.14	$ 0.14	$ 0.27	$ 0.22
Weighted average common shares outstanding (See Note 12):
Basic (in shares)	82,423	76,213	80,491	75,487
Diluted (in shares)	83,513	78,963	81,702	78,703
Comprehensive income (See Note 13)	$ (12,269)	$ 28,131	$ 21,401	$ 40,226