Segment Reporting and Major Customers - Geographic Revenues to External Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Geographic revenues to external revenues by operating segment
Total revenues	$ 1,015,371	$ 1,247,576	$ 3,010,121	$ 3,654,676
United States
Geographic revenues to external revenues by operating segment
Total revenues	814,818	1,066,514	2,422,537	3,135,830
Europe
Geographic revenues to external revenues by operating segment
Total revenues	95,362	80,541	280,096	237,226
Canada
Geographic revenues to external revenues by operating segment
Total revenues	82,704	79,479	241,920	235,059
Other
Geographic revenues to external revenues by operating segment
Total revenues	22,487	21,042	65,568	46,561
Issuer Solutions
Geographic revenues to external revenues by operating segment
Total revenues	470,978	442,230	1,386,939	1,297,478
Issuer Solutions | United States
Geographic revenues to external revenues by operating segment
Total revenues	271,158	261,878	801,464	780,728
Issuer Solutions | Europe
Geographic revenues to external revenues by operating segment
Total revenues	95,196	80,492	279,678	237,039
Issuer Solutions | Canada
Geographic revenues to external revenues by operating segment
Total revenues	82,434	79,098	241,092	234,055
Issuer Solutions | Other
Geographic revenues to external revenues by operating segment
Total revenues	22,190	20,762	64,705	45,656
Merchant Solutions
Geographic revenues to external revenues by operating segment
Total revenues	348,591	625,858	1,016,727	1,798,015
Merchant Solutions | United States
Geographic revenues to external revenues by operating segment
Total revenues	347,858	625,148	1,014,618	1,795,919
Merchant Solutions | Europe
Geographic revenues to external revenues by operating segment
Total revenues	166	49	418	187
Merchant Solutions | Canada
Geographic revenues to external revenues by operating segment
Total revenues	270	381	828	1,004
Merchant Solutions | Other
Geographic revenues to external revenues by operating segment
Total revenues	297	280	863	905
Consumer Solutions
Geographic revenues to external revenues by operating segment
Total revenues	195,802	179,488	606,455	559,183
Consumer Solutions | United States
Geographic revenues to external revenues by operating segment
Total revenues	$ 195,802	$ 179,488	$ 606,455	$ 559,183