Segment Information - Selected Financial Data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 1,370,598	$ 1,294,322	$ 1,258,294
Depreciation and amortization	(133,393)	(140,316)	(122,569)
Stock-based compensation expense	27,242	29,602	36,763
Corporate and unallocated expenses	(185,731)	(205,310)	(198,871)
Interest, net	(33,538)	(45,002)	(52,066)
Other, net	(1,294)	(1,116)	520
Income before income taxes	175,065	98,626	72,210
Bill Payments
Segment Reporting Information [Line Items]
Revenues	592,485	586,482	510,881
Digital Business Banking
Segment Reporting Information [Line Items]
Revenues	60,398	75,475	77,319
Merchant Payments
Segment Reporting Information [Line Items]
Revenues	152,988	149,342	156,452
Fraud Management
Segment Reporting Information [Line Items]
Revenues	43,704	32,942	42,010
Real-Time Payments
Segment Reporting Information [Line Items]
Revenues	77,922	80,654	100,599
Issuing and Acquiring
Segment Reporting Information [Line Items]
Revenues	443,101	369,427	371,033
Operating Segments | Banks
Segment Reporting Information [Line Items]
Revenues	625,125	558,498	590,961
Segment Adjusted EBITDA	372,949	331,445	343,844
Operating Segments | Banks | Bill Payments
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Banks | Digital Business Banking
Segment Reporting Information [Line Items]
Revenues	60,398	75,475	77,319
Operating Segments | Banks | Merchant Payments
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Banks | Fraud Management
Segment Reporting Information [Line Items]
Revenues	43,704	32,942	42,010
Operating Segments | Banks | Real-Time Payments
Segment Reporting Information [Line Items]
Revenues	77,922	80,654	100,599
Operating Segments | Banks | Issuing and Acquiring
Segment Reporting Information [Line Items]
Revenues	443,101	369,427	371,033
Operating Segments | Merchants
Segment Reporting Information [Line Items]
Revenues	152,988	149,342	156,452
Segment Adjusted EBITDA	54,266	53,383	60,820
Operating Segments | Merchants | Bill Payments
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Merchants | Digital Business Banking
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Merchants | Merchant Payments
Segment Reporting Information [Line Items]
Revenues	152,988	149,342	156,452
Operating Segments | Merchants | Fraud Management
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Merchants | Real-Time Payments
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Merchants | Issuing and Acquiring
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Billers
Segment Reporting Information [Line Items]
Revenues	592,485	586,482	510,881
Segment Adjusted EBITDA	129,048	135,144	77,295
Operating Segments | Billers | Bill Payments
Segment Reporting Information [Line Items]
Revenues	592,485	586,482	510,881
Operating Segments | Billers | Digital Business Banking
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Billers | Merchant Payments
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Billers | Fraud Management
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Billers | Real-Time Payments
Segment Reporting Information [Line Items]
Revenues	0	0	0
Operating Segments | Billers | Issuing and Acquiring
Segment Reporting Information [Line Items]
Revenues	$ 0	$ 0	$ 0