Basis of Presentation and Summary of Significant Accounting Policies - Property and Equipment, Goodwill and Intangible Assets (Details) $ in Thousands			1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017 USD ($)	Sep. 30, 2017 item	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Property and Equipment, net
Depreciation expense for property and equipment							$ 120,200	$ 89,100	$ 82,800
Intangible Assets, net
Number of reporting units | item							7
Number of major banks removing direct charges | item			4
Proportion of ATMs held by major banks			33.00%
Goodwill impairment charges							$ 140,038
Income tax (benefit) expense							(9,292)	26,622	$ 39,342
Australia And New Zealand
Intangible Assets, net
Intangible asset impairment				$ 54,500
Goodwill impairment charges		$ 140,000					$ 140,038
Impairment of ATM asset		19,000
Inventory write down		2,500
Income tax (benefit) expense					$ (22,500)	$ (22,500)
Australia And New Zealand | Customer Relationship and Trade name
Intangible Assets, net
Intangible asset impairment		$ 54,500
New ATMs
Property and Equipment, net
Property and equipment useful life							8 years
Other Capitalized Property Plant and Equipment
Property and Equipment, net
Property and equipment useful life							5 years
Capitalized internal development costs							$ 5,500	$ 5,000
Maximum
Property and Equipment, net
Property and equipment useful life							10 years
Intangible Assets, net
Weighted-average discount rate used to estimate fair value of reporting units	17.20%	16.90%
Maximum | Other Capitalized Property Plant and Equipment
Property and Equipment, net
Property and equipment useful life							5 years
Minimum
Property and Equipment, net
Property and equipment useful life							3 years
Intangible Assets, net
Percentage of revenue from ATM charges						80.00%
Weighted-average discount rate used to estimate fair value of reporting units	9.90%	9.30%
Minimum | Other Capitalized Property Plant and Equipment
Property and Equipment, net
Property and equipment useful life							3 years