Product Revenue and Concentration of Credit Risks - Revenue Provisions, and Credits or Payments for Sales-related Deductions (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Sales-related Provisions, Credits and Payments [Roll Forward]
Balance at December 31, 2020	$ 1,290
Current period provisions	9,037
Payments/credits	6,175
Balance at September 30, 2021	4,152
Rebates
Sales-related Provisions, Credits and Payments [Roll Forward]
Balance at December 31, 2020	1,161
Current period provisions	7,134
Payments/credits	4,402
Balance at September 30, 2021	3,893
Trade Discounts, Distributor Fees and Other
Sales-related Provisions, Credits and Payments [Roll Forward]
Balance at December 31, 2020	129
Current period provisions	1,903
Payments/credits	1,773
Balance at September 30, 2021	$ 259