Goodwill and Intangible Assets - Schedule of Carrying Amounts of Indefinite-Lived Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Beginning balance at December 31, 2017	$ 87,768
Ending balance at September 30, 2018	87,505
Total [Member]
Beginning balance at December 31, 2017	87,768
Adjustment related to acquisition of Stack Technology	35
Foreign currency translation	(298)
Ending balance at September 30, 2018	87,505
Commercial [Member]
Beginning balance at December 31, 2017	69,735
Adjustment related to acquisition of Stack Technology
Foreign currency translation
Ending balance at September 30, 2018	69,735
Public Sector [Member]
Beginning balance at December 31, 2017	8,322
Adjustment related to acquisition of Stack Technology
Foreign currency translation
Ending balance at September 30, 2018	8,322
Canada [Member]
Beginning balance at December 31, 2017	4,997
Adjustment related to acquisition of Stack Technology
Foreign currency translation	(127)
Ending balance at September 30, 2018	4,870
United Kingdom [Member]
Beginning balance at December 31, 2017	4,714
Adjustment related to acquisition of Stack Technology	35
Foreign currency translation	(171)
Ending balance at September 30, 2018	$ 4,578

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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