Allowance for Credit Losses - Summary of Finance Receivables by Aging Category (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Accounts receivable	$ 25,084	$ 13,894
Current
Financing Receivable, Allowance for Credit Loss [Line Items]
Accounts receivable	22,328	13,398
31-60 Days
Financing Receivable, Allowance for Credit Loss [Line Items]
Accounts receivable	1,869	489
61-90 Days
Financing Receivable, Allowance for Credit Loss [Line Items]
Accounts receivable	847	7
91 Days and over
Financing Receivable, Allowance for Credit Loss [Line Items]
Accounts receivable	$ 40	$ 0