Basis of Presentation and Summary of Significant Accounting Policies - Cash, A/R, Inventory (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017
Restricted Cash and Cash Equivalents
Restricted cash	$ 48,328	$ 32,213	$ 48,328
Average vault cash	3,900,000	3,500,000
Past due accounts, age for review			90 days
Inventory, Net [Abstract]
Inventory, Gross	16,116	14,471	$ 16,116
Less: Inventory reserves	(1,833)	(1,944)	(1,833)
Inventory, net, Total	14,283	12,527	14,283
ATMs
Inventory, Net [Abstract]
Inventory, Gross	3,181	1,915	3,181
ATM Parts And Supplies
Inventory, Net [Abstract]
Inventory, Gross	$ 12,935	$ 12,556	$ 12,935