UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net (loss) income	$ (15,674)	$ 54,837
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	3,810	1,611
Amortization of premiums on marketable securities	1,693	34
Foreign exchange loss	(160)	1,304
Remeasurement of related party acquisition-related contingent consideration	(9,921)	(20,201)
Remeasurement of related party financing-related contingent consideration	(1,007)	(2,220)
Amortization of debt discount and debt issuance costs	2,019	0
Change in deferred tax and income tax deferred charge	(3,247)	322
Stock-based compensation expense	4,358	4,055
Other adjustments	251	(115)
Net changes in assets and liabilities
Accounts receivable	(157)	(1,446)
Inventories	(242)	(2,489)
Prepaid expenses and other current assets	1,587	(264)
Research and development tax credit receivable	(1,003)	(1,175)
Accounts payable & other current liabilities	5,206	4,931
Accrued expenses	(9,831)	12,747
Earn-out payments for related party contingent consideration in excess of acquisition-date fair value	(11,113)	(16,515)
Royalty payments for related party payable in excess of original fair value	(1,618)	(2,287)
Other assets and liabilities	(2,893)	407
Net cash (used in) provided by operating activities	(37,942)	33,536
Cash flows from investing activities:
Purchases of property and equipment	(99)	(321)
Purchase of intangible asset	(20,000)	0
Proceeds from sales of marketable securities	253,525	51,820
Purchases of marketable securities	(312,638)	(67,743)
Net cash used in investing activities	(79,212)	(16,244)
Cash flows from financing activities:
Earn-out payments for related party contingent consideration	(645)	(665)
Proceeds from debt issuance	143,750	0
Payments for debt issuance costs	(5,760)	0
Share repurchases	(27,637)	(13,081)
Cash proceeds from the issuance of ordinary shares and warrants	3,446	376
Other financing activities, net	6	12
Net cash provided by (used in) financing activities	113,160	(13,358)
Effect of foreign currency exchange rate changes on cash and cash equivalents	(93)	358
Net change in cash and cash equivalents	(4,087)	4,292
Cash and cash equivalents at January 1,	16,564	39,215
Cash and cash equivalents at June 30,	12,477	43,507
Supplemental disclosures of cash flow information:
Interest paid	394	525
Income taxes paid	$ 409	$ 9,605