Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating Activities
Net loss	$ (882)	$ (15,414)
Adjustments to reconcile net loss to net cash and cash equivalents used in operating activities:
Gain from sale of SurgiBot assets, net	(11,996)
Depreciation	660	532
Amortization of intangible assets	2,827	1,636
Amortization of debt discount and debt issuance costs	274	31
Stock-based compensation	1,834	2,139
Deferred tax benefit	(890)	(858)
Change in fair value of warrant liabilities	(1,829)
Change in fair value of contingent consideration	627	1,227
Changes in operating assets and liabilities, net of effect of acquisition:
Accounts receivable	(296)	(753)
Interest receivable	(21)	2
Inventories	(604)	(320)
Other current and long term assets	1,171	(251)
Accounts payable	(217)	(759)
Accrued expenses	(2,871)	(1,161)
Deferred revenue	(86)
Net cash and cash equivalents used in operating activities	(12,299)	(13,949)
Investing Activities
Proceeds related to sale of SurgiBot assets, net	4,496
Purchase of property and equipment	(218)	(501)
Proceeds from sale of property and equipment	17
Net cash and cash equivalents provided by (used in) investing activities	4,295	(501)
Financing Activities
Payment of notes payable		(1,966)
Proceeds from issuance of common stock and warrants, net of issuance costs	11	5,304
Proceeds from issuance of common stock related to sale of SurgiBot assets	3,000
Proceeds from exercise of stock options and warrants	1,712
Net cash and cash equivalents provided by financing activities	4,723	3,338
Effect of exchange rate changes on cash and cash equivalents	88	40
Net decrease in cash, cash equivalents and restricted cash	(3,193)	(11,072)
Cash, cash equivalents and restricted cash, beginning of period	97,606	34,590
Cash, cash equivalents and restricted cash, end of period	94,413	23,518
Supplemental Disclosure for Cash Flow Information
Interest paid	304	233
Supplemental Schedule of Noncash Investing and Financing Activities
Transfer of inventories to property and equipment	71
Issuance of common stock as contingent consideration		$ 5,227
Reclass of warrant liability to common stock and additional paid-in capital	$ 516