Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 86,510	$ 82,630
Product revenue, net
Disaggregation of Revenue [Line Items]
Revenues	85,983	82,068
License and royalty revenues
Disaggregation of Revenue [Line Items]
Revenues	527	562
U.S.
Disaggregation of Revenue [Line Items]
Revenues	75,434	71,488
U.S. | Product revenue, net
Disaggregation of Revenue [Line Items]
Revenues	75,434	71,488
U.S. | License and royalty revenues
Disaggregation of Revenue [Line Items]
Revenues	0	0
International
Disaggregation of Revenue [Line Items]
Revenues	11,076	11,142
International | Product revenue, net
Disaggregation of Revenue [Line Items]
Revenues	10,549	10,580
International | License and royalty revenues
Disaggregation of Revenue [Line Items]
Revenues	$ 527	$ 562