Significant Accounting Policies - Summary of Concentration of Credit Risk (Details) - Sales Revenue - Customer Concentration Risk	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Government Solutions | City of New York Department of Transportation
Concentration Risk [Line Items]
Concentration risk percentage	18.60%	26.70%	18.90%	25.70%
Commercial Services | Hertz Corporation
Concentration Risk [Line Items]
Concentration risk percentage	11.70%	13.30%	11.40%	13.50%
Commercial Services | Avis Budget Group, Inc.
Concentration Risk [Line Items]
Concentration risk percentage	13.20%	13.00%	12.40%	12.20%
Commercial Services | Enterprise Holdings, Inc.
Concentration Risk [Line Items]
Concentration risk percentage	9.70%	12.80%	9.30%	13.50%