Summary of Significant Accounting Policies - Schedule of other income, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Other (expense) income [Abstract]
Foreign currency (loss) / gain	$ (258)	$ 39
Rental loss-net	(865)	(683)
Gain on sale of real estate	649	0
Fair value adjustment contingent consideration	450	1,000
Other	330	273
Other income, net	$ 306	$ 629