Revenue Reserves - Summary of Product Revenue Allowance and Reserve Categories (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($)
Chargebacks and Cash Discount
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ (1,323)
Provision related to current period sales	(2,600)
Credit or payments made during the period	2,584
Ending balance	(1,339)
Distribution Fees, Rebates and Patient Assistance
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning balance	(865)
Provision related to current period sales	(2,047)
Credit or payments made during the period	2,044
Ending balance	$ (868)