Accounts Receivable And Unbilled, Net - Schedule of Allowance for Doubtful Account Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts Notes And Loans Receivable Net Current [Abstract]
Allowance for doubtful accounts - beginning balance	$ (3,222)	$ (1,724)	$ (5,855)
Current year provision	(250)	(2,166)	(642)
Write-offs, recoveries and the effects of foreign currency exchange	2,799	668	4,773
Allowance for doubtful accounts - ending balance	$ (673)	$ (3,222)	$ (1,724)