Fair Value of Financial Instruments (Details) $ in Thousands	Dec. 31, 2016 USD ($) Letter Bond Contract	Dec. 31, 2015 USD ($)
Performance Bond [Abstract]
Unrestricted cash	$ 15,300	$ 5,400
Number of standby letters of credit | Letter	4
Number of surety bonds | Bond	1
Letter of credit and surety bonds	$ 1,000
Number of performance and bid bonds issued in relation to contracts | Contract	4
Number of stand by letters of credit deposited in escrow accounts | Letter	4
Assets and liabilities measured at fair value [Abstract]
Money market funds	$ 16,435	8,979
Foreign exchange contracts - Assets	141	121
Total assets	16,576	9,100
Foreign exchange contracts - Liabilities	(20)	(57)
Contingent consideration liability	(2,105)	(3,732)
Total liabilities	(2,125)	(3,789)
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets and liabilities measured at fair value [Abstract]
Money market funds	16,435	8,979
Foreign exchange contracts - Assets	0	0
Total assets	16,435	8,979
Foreign exchange contracts - Liabilities	0	0
Contingent consideration liability	0	0
Total liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member]
Assets and liabilities measured at fair value [Abstract]
Money market funds	0	0
Foreign exchange contracts - Assets	141	121
Total assets	141	121
Foreign exchange contracts - Liabilities	(20)	(57)
Contingent consideration liability	0	0
Total liabilities	(20)	(57)
Significant Unobservable Inputs (Level 3) [Member]
Assets and liabilities measured at fair value [Abstract]
Money market funds	0	0
Foreign exchange contracts - Assets	0	0
Total assets	0	0
Foreign exchange contracts - Liabilities	0	0
Contingent consideration liability	(2,105)	(3,732)
Total liabilities	$ (2,105)	$ (3,732)