Accounts Receivable and Revenue Concentration - Concentration of Credit Risk (Details) - Customer concentration risk	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenue
Concentration Risk [Line Items]
Concentration risk	100.00%	100.00%	100.00%	100.00%
Revenue | Customer A
Concentration Risk [Line Items]
Concentration risk	50.80%	13.60%	46.50%	15.10%
Revenue | Customer B
Concentration Risk [Line Items]
Concentration risk	17.70%	63.90%	31.30%	58.00%
Revenue | Customer C
Concentration Risk [Line Items]
Concentration risk	12.30%	7.80%	10.30%	8.40%
Revenue | Customer D
Concentration Risk [Line Items]
Concentration risk	7.40%	2.70%	4.00%	3.10%
Revenue | Customer E
Concentration Risk [Line Items]
Concentration risk	6.20%	9.60%	4.30%	11.90%
Revenue | Remaining customers
Concentration Risk [Line Items]
Concentration risk	5.60%	2.40%	3.60%	3.50%
Accounts receivable
Concentration Risk [Line Items]
Concentration risk			100.00%		100.00%
Accounts receivable | Customer A
Concentration Risk [Line Items]
Concentration risk			0.60%		85.90%
Accounts receivable | Customer B
Concentration Risk [Line Items]
Concentration risk			28.30%		13.50%
Accounts receivable | Customer C
Concentration Risk [Line Items]
Concentration risk			35.50%		0.40%
Accounts receivable | Customer D
Concentration Risk [Line Items]
Concentration risk			9.20%		0.00%
Accounts receivable | Customer E
Concentration Risk [Line Items]
Concentration risk			8.10%		0.00%
Accounts receivable | Remaining customers
Concentration Risk [Line Items]
Concentration risk			18.30%		0.20%