Operating Segments - Customers (Details) - customer	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Concentration risk
Number of customers	18	23
Customer Concentration risk
Concentration risk
Number of customers	1	4
Threshold concentration risk for reporting (as a percent)	10.00%	10.00%
Total Revenue | Customer Concentration risk | Customer One
Concentration risk
Concentration risk (as a percent)	54.00%	27.00%
Total Revenue | Customer Concentration risk | Customer Two
Concentration risk
Concentration risk (as a percent)		22.00%
Total Revenue | Customer Concentration risk | Customer Three
Concentration risk
Concentration risk (as a percent)		16.00%
Total Revenue | Customer Concentration risk | Customer Four
Concentration risk
Concentration risk (as a percent)		13.00%