Acquisition of SafeOp Surgical, Inc. - Schedule of Unaudited Pro Forma Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Business Combinations [Abstract]
Revenue	$ 22,042	$ 24,436	$ 43,377	$ 52,460
Loss from continuing operations	(6,785)	(3,573)	(9,467)	(10,229)
Net loss	$ (6,797)	$ (3,641)	$ (9,541)	$ (10,388)
Net loss per share, basic and diluted	$ (0.16)	$ (0.22)	$ (0.23)	$ (0.66)