CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME / (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Total revenue, net	$ 379,095	$ 365,854	$ 1,122,430	$ 1,089,126
Costs and expenses:
Cost of goods sold	142,636	143,245	415,219	425,032
Research and development	19,003	20,309	53,280	57,742
In-process research and development	59,889	0	61,566	0
Selling, general and administrative	173,098	173,355	513,345	513,518
Intangible asset amortization	5,056	5,268	21,340	15,944
Total costs and expenses	399,682	342,177	1,064,750	1,012,236
Operating income (loss)	(20,587)	23,677	57,680	76,890
Interest income	2,913	75	8,051	325
Interest expense	(13,962)	(14,478)	(40,495)	(50,750)
Other income, net	4,127	1,750	8,461	6,422
Income (loss) before income taxes	(27,509)	11,024	33,697	32,887
Provision (benefit) for income taxes	101	(2,271)	(1,185)	(2,776)
Net income (loss)	$ (27,610)	$ 13,295	$ 34,882	$ 35,663
Net income (loss) per share
Basic (in dollars per share)	$ (0.32)	$ 0.16	$ 0.41	$ 0.43
Diluted (in dollars per share)	$ (0.32)	$ 0.15	$ 0.40	$ 0.43
Weighted average common shares outstanding (See Note 13):
Basic (in shares)	85,688	85,193	85,536	82,058
Diluted (in shares)	85,688	86,299	86,581	83,142
Comprehensive income (loss) (See Note 14)	$ (46,521)	$ 12,330	$ (7,288)	$ 33,731