Revenues - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of revenue
Revenue	$ 1,035,485	$ 1,007,580	$ 2,070,016	$ 1,994,750
U.S. dollar
Disaggregation of revenue
Revenue	935,130	916,278	1,871,192	1,805,755
British Pound Sterling
Disaggregation of revenue
Revenue	67,142	59,098	132,294	122,219
Euro
Disaggregation of revenue
Revenue	25,750	25,419	51,361	52,016
Other
Disaggregation of revenue
Revenue	7,463	6,785	15,169	14,760
Volume-based revenues
Disaggregation of revenue
Revenue	769,575	752,462	1,541,294	1,480,402
Non-volume related revenues
Disaggregation of revenue
Revenue	265,910	255,118	528,722	514,348
Issuer Solutions
Disaggregation of revenue
Revenue	472,706	458,601	942,865	915,960
Issuer Solutions | U.S. dollar
Disaggregation of revenue
Revenue	372,674	367,489	744,674	727,359
Issuer Solutions | British Pound Sterling
Disaggregation of revenue
Revenue	67,142	59,098	132,294	122,219
Issuer Solutions | Euro
Disaggregation of revenue
Revenue	25,750	25,419	51,361	52,016
Issuer Solutions | Other
Disaggregation of revenue
Revenue	7,140	6,595	14,536	14,366
Issuer Solutions | Volume-based revenues
Disaggregation of revenue
Revenue	231,265	223,677	461,476	442,949
Issuer Solutions | Non-volume related revenues
Disaggregation of revenue
Revenue	241,441	234,924	481,389	473,011
Merchant Solutions
Disaggregation of revenue
Revenue	366,636	348,714	711,817	668,137
Merchant Solutions | U.S. dollar
Disaggregation of revenue
Revenue	366,313	348,524	711,184	667,743
Merchant Solutions | Other
Disaggregation of revenue
Revenue	323	190	633	394
Merchant Solutions | Volume-based revenues
Disaggregation of revenue
Revenue	342,651	329,295	665,464	628,242
Merchant Solutions | Non-volume related revenues
Disaggregation of revenue
Revenue	23,985	19,419	46,353	39,895
Consumer Solutions
Disaggregation of revenue
Revenue	196,143	200,265	415,334	410,653
Consumer Solutions | U.S. dollar
Disaggregation of revenue
Revenue	196,143	200,265	415,334	410,653
Consumer Solutions | Volume-based revenues
Disaggregation of revenue
Revenue	195,659	199,490	414,354	409,211
Consumer Solutions | Non-volume related revenues
Disaggregation of revenue
Revenue	$ 484	$ 775	$ 980	$ 1,442