Variable Interest Entities - Summary of Amounts and Classification of Assets and Liabilities of VIE (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 75,303	$ 86,907
Unbilled receivables	5,260	4,426
Prepaid and other current assets	2,734	4,144
Total assets	115,821	144,701
Accounts payable	1,135	1,287
Deferred revenue	5,321	20,954
Total liabilities	63,522	83,950
VIE, Primary beneficiary
Variable Interest Entity [Line Items]
Cash and cash equivalents	623	1,206
Accounts receivable	420	0
Unbilled receivables	83	272
Prepaid and other current assets	20	46
Total assets	1,146	1,524
Accounts payable	9	9
Accrued liabilities	12	234
Deferred revenue	41	76
Intercompany payable	1,396	1,695
Total liabilities	$ 1,458	$ 2,014