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Acquisition - Additional Information (Details) customer in Thousands		12 Months Ended
	May 09, 2019 USD ($) customer	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Operating income		$ 209,897,000	$ 144,744,000	$ 123,756,000
SpeedPay
Business Acquisition [Line Items]
Acquisition purchase price	$ 754,100,000
Acquisition-related costs				22,200,000
Acquisition-related revenue				227,700,000
Operating income				$ 24,900,000
SpeedPay \| Delayed Draw Term Loan \| Credit Agreement \| Bank of America
Business Acquisition [Line Items]
Debt instrument, face amount	500,000,000
SpeedPay \| Revolving Credit Facility \| Credit Agreement \| Bank of America
Business Acquisition [Line Items]
Line of credit, carrying amount	$ 250,000,000
SpeedPay \| United States
Business Acquisition [Line Items]
Number of customers \| customer	4