Revenue Recognition - Gross-to-Net Revenue Adjustments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Product revenue, net	$ 20,074	$ 0	$ 20,074	$ 0
Accounts payable and accrued expenses	59,862		59,862		$ 60,860
Gross product revenue
Disaggregation of Revenue [Line Items]
Product revenue, net			24,198
Government rebates
Disaggregation of Revenue [Line Items]
Product revenue, net			(2,709)
Chargebacks and distributor service fees
Disaggregation of Revenue [Line Items]
Product revenue, net			(1,173)
Sales returns and allowances
Disaggregation of Revenue [Line Items]
Product revenue, net			(242)
Total gross-to-net adjustments
Disaggregation of Revenue [Line Items]
Product revenue, net			(4,124)
Accounts payable and accrued expenses	$ 2,700		$ 2,700