Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net loss	$ (129,752)	$ (35,131)
Adjustments to reconcile net loss to net cash used in operating activities:
Bad debt expense	383	109
Depreciation and amortization	6,566	4,561
Stock-based compensation	9,641	7,169
Change in fair value of derivative liabilities	43,831	0
Change in fair value of contingent consideration related to acquisition	100	200
Accretion of interest & amortization of deferred financing costs on convertible notes	7,037	2,999
Non-cash foreign exchange loss (gain)	838	(593)
Changes in operating assets and liabilities:
Restricted cash	(2,001)	0
Accounts receivable and other receivables	(3,883)	(1,452)
Inventories	2,083	(1,889)
Prepaid expenses and other current assets	535	148
Accounts payable	(6,607)	4,730
Accrued payroll	7,660	633
Accrued expenses and other liabilities	3,498	182
Net cash used in operating activities	(60,071)	(18,334)
Cash flows from investing activities:
Purchases of marketable securities	(20,976)	(52,420)
Maturities of marketable securities	37,850	79,340
Purchases of property and equipment	(2,051)	(3,572)
Acquisition of business, net of cash acquired of $24,012	(60,622)	0
Net cash (used in) provided by investing activities	(45,799)	23,348
Cash flows from financing activities:
Deferred financing costs	(917)	0
Proceeds from sale of common stock under employee stock purchase plan	2,520	2,787
Proceeds from exercise of stock options	1,777	1,631
Minimum tax withholding paid on behalf of employees for restricted stock units	(134)	(291)
Net cash provided by financing activities	3,246	4,127
Effect of exchange rate changes on cash and cash equivalents	93	(535)
Net (decrease) increase in cash and cash equivalents	(102,531)	8,606
Cash and cash equivalents, beginning of period	124,553	26,798
Cash and cash equivalents, end of period	22,022	35,404
Supplemental disclosure of cash flow information:
Cash paid for interest	3,088	976
Cash paid for income taxes	214	162
Non-cash investing and financing activities:
Landlord funded leasehold improvements	0	46
Acquisition of property and equipment included in accounts payable	64	43
Fair value of common stock issued for business acquisition	100,812	0
Fair value of warrants issued for business acquisition	$ 44	$ 0