Related Party Transactions - Additional Information (Details) $ / shares in Units, $ in Thousands				3 Months Ended
		Jan. 27, 2020 USD ($) $ / shares	Apr. 26, 2019 $ / shares	Mar. 31, 2022 USD ($) yr $ / shares shares	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Jun. 30, 2021 yr	Oct. 17, 2018 USD ($)
Related Party Transaction [Line Items]
Tax receivable agreement, amount payable, current				$ 5,107		$ 5,107
Tax receivable agreement, amount payable, non-current				56,615		56,615
Term of volatility and risk free rates utilizing a peer group | yr							5
Revenue				$ 170,385	$ 89,858
Redflex Irish Investments Pty Ltd
Related Party Transaction [Line Items]
Percentage of Non-Voting Interest Acquired				16.00%
Cost method investment				$ 3,700		$ 3,700
Revenue				$ 300
Minimum | Platinum Stockholder | Common Stock Price Greater than $13.00
Related Party Transaction [Line Items]
Common stock price threshold trading days			10 days
Minimum | Platinum Stockholder | Common Stock Price Greater than $15.50
Related Party Transaction [Line Items]
Common stock price threshold trading days		10 days
Maximum | Platinum Stockholder | Common Stock Price Greater than $13.00
Related Party Transaction [Line Items]
Common stock price threshold trading days			20 days
Maximum | Platinum Stockholder | Common Stock Price Greater than $15.50
Related Party Transaction [Line Items]
Common stock price threshold trading days		20 days
Verra Mobility Business Combination
Related Party Transaction [Line Items]
Tax Receivable Agreement, portion of net cash savings paid out				50.00%
Tax Receivable Agreement, portion of net cash savings retained				50.00%
Estimated maximum benefit to be paid to tax receivable agreement				$ 70,000
Tax receivable agreement, amount payable				61,700
Tax receivable agreement, amount payable, current				5,100
Tax receivable agreement, amount payable, non-current				$ 56,600
Contingency period				5 years
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $13.00 and $15.50
Related Party Transaction [Line Items]
Earn-out shares issuable if condition met | shares				5,000,000
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $13.00 and $15.50 | Common Stock Including Additional Paid in Capital
Related Party Transaction [Line Items]
Earn-out shares issued value		$ 36,600
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $13.00
Related Party Transaction [Line Items]
Common stock price | $ / shares			$ 13.00
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $13.00 | Potential Future Shares
Related Party Transaction [Line Items]
Earn-out shares issued value				$ 0
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $15.50
Related Party Transaction [Line Items]
Common stock price | $ / shares		$ 15.50
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $15.50 | Common Stock Contingent Consideration
Related Party Transaction [Line Items]
Earn-out shares issued value		$ (36,600)
Verra Mobility Business Combination | Platinum Stockholder | Common Stock Price Greater than $15.50 | Potential Future Shares
Related Party Transaction [Line Items]
Earn-out shares issued value				5,000
Verra Mobility Business Combination | Platinum Stockholder | Earn-Out Agreement
Related Party Transaction [Line Items]
Contingent consideration				$ 36,600				$ 73,150
Term of volatility and risk free rates utilizing a peer group | yr				5
Verra Mobility Business Combination | Platinum Stockholder | Earn-Out Agreement | Earn-Out Scenario Five
Related Party Transaction [Line Items]
Earn-out shares issuable if condition met | shares				0
Verra Mobility Business Combination | Platinum Stockholder | Earn-Out Agreement | Common Stock Price Greater than $13.00
Related Party Transaction [Line Items]
Earn-out shares issuable if condition met | shares				2,500,000
Common stock price | $ / shares	[1]			$ 13.00
Verra Mobility Business Combination | Platinum Stockholder | Earn-Out Agreement | Common Stock Price Greater than $15.50
Related Party Transaction [Line Items]
Earn-out shares issuable if condition met | shares				2,500,000
Common stock price | $ / shares	[1]			$ 15.50
Verra Mobility Business Combination | Minimum
Related Party Transaction [Line Items]
Common stock price threshold trading days				10 days
Verra Mobility Business Combination | Minimum | Platinum Stockholder | Common Stock Price Greater than $13.00
Related Party Transaction [Line Items]
Common stock price threshold trading days			10 days
Verra Mobility Business Combination | Minimum | Platinum Stockholder | Common Stock Price Greater than $15.50
Related Party Transaction [Line Items]
Common stock price threshold trading days		10 days
Verra Mobility Business Combination | Maximum
Related Party Transaction [Line Items]
Common stock price threshold trading days				20 days
Verra Mobility Business Combination | Maximum | Platinum Stockholder | Common Stock Price Greater than $13.00
Related Party Transaction [Line Items]
Common stock price threshold trading days			20 days
Verra Mobility Business Combination | Maximum | Platinum Stockholder | Common Stock Price Greater than $15.50
Related Party Transaction [Line Items]
Common stock price threshold trading days		20 days
Verra Mobility Business Combination | Maximum | Platinum Stockholder | Earn-Out Agreement
Related Party Transaction [Line Items]
Earn-out shares issuable if condition met | shares				10,000,000

[1] The first and second tranches of Earn-Out Shares have been issued, as discussed below.