CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Total revenue, net	$ 359,690	$ 357,082
Costs and expenses:
Cost of goods sold	128,912	144,222
Research and development	18,321	18,325
Selling, general and administrative	174,870	163,566
Intangible asset amortization	5,279	5,390
Total costs and expenses	327,382	331,503
Operating income	32,308	25,579
Interest income	2,428	76
Interest expense	(13,149)	(18,768)
Other income, net	3,236	2,245
Income before income taxes	24,823	9,132
Income tax benefit	(7,933)	(1,860)
Net income	$ 32,756	$ 10,992
Net income per share
Basic (in dollars per share)	$ 0.38	$ 0.14
Diluted (in dollars per share)	$ 0.38	$ 0.14
Weighted average common shares outstanding (See Note 13):
Basic (in shares)	85,343	78,552
Diluted (in shares)	86,258	79,834
Comprehensive income (See Note 14)	$ 21,520	$ 32,604