Product Revenue and Reserves for Variable Consideration - Product Revenue Allowance and Reserve Categories (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 41,363	$ 31,543
Current provisions related to sales in current year	78,863	74,087
Adjustments related to prior year sales	806	651
Credits/payments made	(73,098)	(62,177)
Ending balance	47,934	44,104
Chargebacks and Discounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	802	738
Current provisions related to sales in current year	6,084	5,055
Adjustments related to prior year sales	(6)	(31)
Credits/payments made	(5,588)	(4,995)
Ending balance	1,292	767
Rebates, Fees and other Deductions
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	39,912	30,552
Current provisions related to sales in current year	69,163	66,348
Adjustments related to prior year sales	812	638
Credits/payments made	(63,795)	(54,945)
Ending balance	46,092	42,593
Returns
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	649	253
Current provisions related to sales in current year	3,616	2,684
Adjustments related to prior year sales	0	44
Credits/payments made	(3,715)	(2,237)
Ending balance	$ 550	$ 744