Total number of customers.

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Face (par) amount of debt instrument at time of issuance.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisition - Additional Information (Details) customer in Thousands		3 Months Ended		6 Months Ended
	May 09, 2019 USD ($) customer	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Apr. 05, 2019 USD ($)
Revolving Credit Facility \| Credit Agreement
Business Acquisition [Line Items]
Line of credit, carrying amount		$ 200,000,000.0		$ 200,000,000.0
SpeedPay
Business Acquisition [Line Items]
Acquisition purchase price	$ 754,100,000
Acquisition-related costs			$ 16,600,000		$ 21,300,000
Acquisition-related revenue		80,200,000	49,300,000	168,900,000	49,300,000
Acquisition-related operating income		$ 15,000,000.0	$ 7,600,000	$ 27,300,000	$ 7,600,000
SpeedPay \| Bank of America \| Delayed Draw Term Loan \| Credit Agreement
Business Acquisition [Line Items]
Debt instrument, face amount						$ 500,000,000.0
SpeedPay \| Bank of America \| Revolving Credit Facility \| Credit Agreement
Business Acquisition [Line Items]
Line of credit, carrying amount						$ 250,000,000.0
SpeedPay \| U.S.
Business Acquisition [Line Items]
Number of customers \| customer	4