Geographic Information (Revenue by Geographic Locations) (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) Reportable_Segments	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | Reportable_Segments			1
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)	$ 37,239,000		$ 66,366,000
Long-lived assets	1,029,348,000	$ 729,209,000	1,029,348,000	$ 729,209,000	$ 1,029,348,000
Operating revenue	124,626,000	87,387,000	232,856,000	166,490,000
Increase (Decrease) in Deferred Income Taxes			1,321,000	5,877,000
Goodwill, Acquired During Period			192,271,000			$ 233,095,000
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			(6,800,000)
Long-lived assets	395,748,000	391,308,000	395,748,000	391,308,000	395,748,000
Operating revenue	48,400,000	52,900,000	98,302,000	105,079,000
Long Lived Assets, Increase (Decrease)					4,400,000
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			(1,100,000)
Long-lived assets	6,210,000	6,484,000	6,210,000	6,484,000	6,210,000
Operating revenue	1,456,000	2,034,000	3,056,000	4,142,000
BRAZIL
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			2,300,000
Effect of Exchange Rate on Revenue			(800,000)
Latin America
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	19,179,000	23,283,000	19,179,000	23,283,000	19,179,000
Operating revenue	5,161,000	4,319,000	10,555,000	8,218,000
Long Lived Assets, Increase (Decrease)					$ (4,100,000)
Foreign Currency Translation Gain (Loss), Percent					(14.80%)
Foreign Currency Translation Related To Long Lived Assets					$ (1,200,000)
Australia
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			1,700,000
Long-lived assets	1,640,000	1,261,000	1,640,000	1,261,000	1,640,000
Operating revenue	8,740,000	7,617,000	18,227,000	16,516,000
Effect of Exchange Rate on Revenue			400,000
Singapore
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	17,926,000	17,441,000	17,926,000	17,441,000	17,926,000
Operating revenue	1,924,000	1,394,000	4,140,000	3,125,000
New Zealand
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	272,000	257,000	272,000	257,000	272,000
Operating revenue	526,000	543,000	1,013,000	1,023,000
India
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			63,400,000
Long-lived assets	507,404,000	213,135,000	507,404,000	213,135,000	507,404,000
Operating revenue	51,351,000	14,379,000	83,354,000	19,999,000
Long Lived Assets, Increase (Decrease)					307,100,000
Increase In Value Of Long Lived Assets From Business Acquisitions					313,300,000
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	25,555,000	22,254,000	25,555,000	22,254,000	25,555,000
Operating revenue	3,841,000	4,201,000	7,872,000	8,388,000
Long Lived Assets, Increase (Decrease)					(3,300,000)
Dubai [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	54,375,000	53,786,000	54,375,000	53,786,000	54,375,000
Operating revenue	0	0	4,000	0
INDONESIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	97,000	0	97,000	0	97,000
Operating revenue	1,828,000	0	3,369,000	0
PHILIPPINES
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	912,000	0	912,000	0	912,000
Operating revenue	1,245,000	0	2,593,000	0
UNITED ARAB EMIRATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	30,000	0	30,000	0	$ 30,000
Operating revenue	$ 154,000	$ 0	371,000	$ 0
ItzCash, Youfirst, WallStreet, PML, Via, and Transcorp [Member] | India
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			60,800,000
e- governance contracts [Member] | India
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue, Net, Increase (Decrease)			$ 2,500,000