Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating activities
Net loss	$ (68,771)	$ (78,096)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	638	792
Amortization of right-of-use assets	1,171	459
Accretion of discount on investment securities	(139)	(262)
Non-cash interest expense	5,066	6,481
Stock-based compensation expense, net of capitalized labor	9,480	17,894
Remeasurement loss (gain) on embedded derivatives liabilities	3,169	(472)
Provision for excess and obsolete inventories	2,110	3,945
Foreign currency remeasurement loss	252	0
Changes in operating assets and liabilities:
Inventories	(15,601)	1,498
Trade and other receivables, net	6,137	(5,938)
Unbilled - collaboration and license revenue	375	3,563
Prepaid and other current assets	(2,328)	1,986
Prepaid and other long-term assets	3,230	(11,042)
Accounts payable	585	(4,489)
Accrued research and development	(2,019)	(1,455)
Accrued and other liabilities	(10,243)	3,225
Deferred revenue	(491)	303
Notes payable and long term royalty-based debt	(3,721)	(2,027)
Net cash used in operating activities	(71,100)	(63,635)
Investing activities
Capital expenditures, net	(963)	(327)
Purchases of investments	(46,473)	(41,708)
Proceeds from maturities of investments	100,363	124,138
Net cash provided by investing activities	52,927	82,103
Financing activities
Proceeds from debt issuance, net	0	59,203
Proceeds from issuance of common stock pursuant to equity award plans	379	10,637
Payments of long-term obligation to collaborator	(278)	0
Net cash provided by financing activities	101	69,840
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(23)	0
Net (decrease) increase in cash, cash equivalents and restricted cash	(18,095)	88,308
Cash, cash equivalents and restricted cash at beginning of period	218,650	140,013
Cash, cash equivalents and restricted cash at end of period	$ 200,555	$ 228,321