Accounting Policies - Percentage of Net Product Sales and Accounts Receivable Balance (Details) - Customer Concentration Risk	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021
Revenue Benchmark
Product Information [Line Items]
Concentration risk percentage	99.20%	99.10%
Revenue Benchmark | Largest Customer
Product Information [Line Items]
Concentration risk percentage	50.20%	48.90%
Revenue Benchmark | Second Largest Customer
Product Information [Line Items]
Concentration risk percentage	30.90%	31.70%
Revenue Benchmark | Third Largest Customer
Product Information [Line Items]
Concentration risk percentage	18.10%	18.50%
Accounts Receivable
Product Information [Line Items]
Concentration risk percentage		99.60%
Accounts Receivable | Largest Customer
Product Information [Line Items]
Concentration risk percentage		48.90%
Accounts Receivable | Second Largest Customer
Product Information [Line Items]
Concentration risk percentage		37.40%
Accounts Receivable | Third Largest Customer
Product Information [Line Items]
Concentration risk percentage		13.30%