Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities:
Net loss	$ (35,131)	$ (17,636)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	4,561	1,938
Stock-based compensation	7,169	5,568
Change in fair value of contingent consideration related to acquisition	200	(8,228)
Accretion of interest on convertible note	2,645	2,453
Amortization of deferred financing costs	354	303
Non-cash foreign exchange (gain) loss	(593)	4,050
Changes in operating assets and liabilities:
Accounts receivable and other receivables	(1,343)	(1,343)
Inventories	(1,889)	(8,512)
Prepaid expenses and other current assets	148	(880)
Accounts payable	4,730	2,208
Accrued payroll	633	1,576
Accrued expenses and other liabilities	182	3,231
Net cash used in operating activities	(18,334)	(15,272)
Cash flows from investing activities:
Purchases of marketable securities	(52,420)	(107,454)
Maturities of marketable securities	79,340	64,820
Purchases of property and equipment	(3,572)	(9,902)
Net cash provided by (used in) investing activities	23,348	(52,536)
Cash flows from financing activities:
Proceeds from sale of common stock under employee stock purchase plan	2,787	1,446
Proceeds from exercise of stock options	1,631	1,596
Minimum tax withholding paid on behalf of employees for restricted stock units	(291)	(2,320)
Net cash provided by financing activities	4,127	722
Effect of exchange rate changes on cash and cash equivalents	(535)	(529)
Net increase (decrease) in cash and cash equivalents	8,606	(67,615)
Cash and cash equivalents, beginning of period	26,798	95,152
Cash and cash equivalents, end of period	35,404	27,537
Supplemental disclosure of cash flow information:
Cash paid for interest	976	1,047
Cash paid for income taxes	162	239
Non-cash investing and financing activities:
Landlord funded leasehold improvements	46	6,669
Fair value of Nellix Milestone Shares (note 9)	0	38,372
Acquisition of property and equipment included in accounts payable	$ 43	$ 2,351