Product Revenue and Reserves for Variable Consideration - Product Revenue Allowance and Reserve Categories (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 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	119,209	119,438
Adjustments related to prior year sales	(1,591)	2,946
Credits/payments made	(113,090)	(110,499)
Ending balance	45,891	43,428
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	8,911	7,833
Adjustments related to prior year sales	(1)	(85)
Credits/payments made	(8,593)	(7,701)
Ending balance	1,119	785
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	105,432	107,421
Adjustments related to prior year sales	(1,590)	703
Credits/payments made	(99,518)	(96,807)
Ending balance	44,236	41,869
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	4,866	4,184
Adjustments related to prior year sales	0	2,328
Credits/payments made	(4,979)	(5,991)
Ending balance	$ 536	$ 774