CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net loss	$ (27,772)	$ (18,789)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,569	1,550
Share-based compensation expense	4,294	2,527
Change in fair value of derivative financial instruments and contingent consideration	2,027	(756)
Unrealized foreign exchange gains	(1,820)	(131)
Change in deferred taxes		(92)
Change in lease incentives		(72)
Changes in operating assets and liabilities:
Accounts receivable and accrued income, prepaid expenses and other current assets	(2,763)	(1,142)
Accounts payable	(246)	681
Accrued expenses and other liabilities	(1,190)	(2,656)
Deferred revenue	(537)	(2,560)
Net cash used in operating activities	(26,438)	(21,440)
Cash flows from investing activities
Purchases of intangible assets	(996)
Purchase of property, plant and equipment	(234)	(648)
Net cash used in investing activities	(1,230)	(648)
Cash flows from financing activities
Proceeds from issuance of shares related to employee stock option and purchase plans	2,178	1,562
Proceeds from exercise of warrants	500
Net cash generated from financing activities	2,678	1,562
Currency effect cash, cash equivalents and restricted cash	(635)	1,997
Net decrease in cash, cash equivalents and restricted cash	(25,625)	(18,529)
Cash, cash equivalents and restricted cash at beginning of period	237,342	161,851
Cash, cash equivalents and restricted cash at the end of period	211,717	143,322
Supplemental cash flow disclosures:
Total cash, cash equivalents and restricted cash	237,342	161,851
Cash paid for interest	$ 751	$ 409