Concentration of Credit Risk (Details) - customer	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Concentration Risk [Line Items]
Percentage of U.S. demand supplied by company	1.00%
Customer Concentration Risk | Minimum
Concentration Risk [Line Items]
Number of customers	3
Customer Concentration Risk | Maximum
Concentration Risk [Line Items]
Number of customers	5
Customer Concentration Risk | Sales Revenue, Goods, Net
Concentration Risk [Line Items]
Concentration risk, percentage	50.00%
Customer Concentration Risk | Sales Revenue, Goods, Net | Customer One
Concentration Risk [Line Items]
Concentration risk, percentage	27.30%	22.80%	18.20%
Customer Concentration Risk | Sales Revenue, Goods, Net | Customer Two
Concentration Risk [Line Items]
Concentration risk, percentage	14.10%	17.10%	16.50%
Customer Concentration Risk | Sales Revenue, Goods, Net | Customer Three
Concentration Risk [Line Items]
Concentration risk, percentage		10.80%	15.90%
Customer Concentration Risk | Sales Revenue, Goods, Net | Customer Four
Concentration Risk [Line Items]
Concentration risk, percentage		10.70%	10.60%
Customer Concentration Risk | Accounts Receivable | Customer One
Concentration Risk [Line Items]
Concentration risk, percentage	18.40%	19.10%	20.90%
Customer Concentration Risk | Accounts Receivable | Customer Two
Concentration Risk [Line Items]
Concentration risk, percentage	11.90%	15.00%	14.00%
Customer Concentration Risk | Accounts Receivable | Customer Three
Concentration Risk [Line Items]
Concentration risk, percentage		11.10%	10.10%
Customer Concentration Risk | Accounts Receivable | Customer Four
Concentration Risk [Line Items]
Concentration risk, percentage		10.40%