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Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands				12 Months Ended
	Jan. 13, 2021	Nov. 30, 2020	Apr. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Combination Segment Allocation [Line Items]
Provision for credit losses				$ 146,063	$ 67,732	$ 50,287
International
Business Combination Segment Allocation [Line Items]
Provision for credit losses				90,100
Roger \| Subsequent Event
Business Combination Segment Allocation [Line Items]
Aggregate purchase price	$ 40,000
2019 Acquisitions
Business Combination Segment Allocation [Line Items]
Aggregate purchase price				$ 417,000
NvoicePay
Business Combination Segment Allocation [Line Items]
Aggregate purchase price			$ 208,000
Cash acquired			4,100
Series of Individually Immaterial Business Acquisitions
Business Combination Segment Allocation [Line Items]
Aggregate purchase price		$ 78,000			209,000
Non-compete agreements \| NvoicePay
Business Combination Segment Allocation [Line Items]
Estimated fair value, non-compete agreements			$ 10,700
Non-compete agreements \| Series of Individually Immaterial Business Acquisitions
Business Combination Segment Allocation [Line Items]
Estimated fair value, non-compete agreements		$ 3,800			$ 8,100