Total number of customers.

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

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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		9 Months Ended
	May 09, 2019 USD ($) customer	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Apr. 05, 2019 USD ($)
Revolving Credit Facility \| Credit Agreement
Business Acquisition [Line Items]
Line of credit, carrying amount		$ 160,000,000.0		$ 160,000,000.0
SpeedPay
Business Acquisition [Line Items]
Acquisition purchase price	$ 754,100,000
Acquisition-related costs			$ 900,000		$ 22,200,000
Acquisition-related revenue		$ 80,300,000	87,700,000	$ 249,200,000	137,100,000
Acquisition-related operating income			$ 7,500,000		$ 15,200,000
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