Commitments and Contingencies - Concentration of Credit Risk (Details) - customer	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Ten largest customers
Concentration of Credit Risk
Number of customers	10
Accounts Receivable | Credit Concentration Risk | Ten largest customers
Concentration of Credit Risk
Concentration Risk (as a percent)	67.00%	61.00%
Accounts Receivable | Credit Concentration Risk | Customer A
Concentration of Credit Risk
Concentration Risk (as a percent)	16.00%	22.00%
Accounts Receivable | Credit Concentration Risk | Customer B
Concentration of Credit Risk
Concentration Risk (as a percent)	21.00%
Net Sales | Credit Concentration Risk | Customer A
Concentration of Credit Risk
Concentration Risk (as a percent)	11.00%
Net Sales | Credit Concentration Risk | Customer C
Concentration of Credit Risk
Concentration Risk (as a percent)		12.00%
Net Sales | Credit Concentration Risk | Customer D
Concentration of Credit Risk
Concentration Risk (as a percent)			21.00%