Fair Value Measurements - Summary of Changes in the Fair Value of the Liability (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Payment of contingent consideration			$ (897)	$ (627)
Fair value adjustment of contingent consideration	$ (246)	$ 43	(536)	$ 900
NLEX [Member] | Contingent Consideration [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Beginning balance			2,733
Payment of contingent consideration			(897)
Fair value adjustment of contingent consideration			536
Ending balance	$ 2,372		$ 2,372