Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities
Net loss	$ (196,200)	$ (261,658)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation and amortization	2,337	2,303
Amortization of right-of-use asset	2,056
Accretion of discount on investment securities	(946)	(1,519)
Non-cash interest expense	21,216	12,642
Stock-based compensation expense, net of capitalized labor	41,193	35,587
Remeasurement gain on embedded derivatives liabilities	(3,447)	(3,668)
Provision for excess and obsolete inventories	4,131	2,246
Loss on impairment of intangibles	3,151	0
Others	67	14
Changes in operating assets and liabilities:
Inventories	2,312	(15,597)
Trade and other receivables, net	(12,387)	(694)
Unbilled - collaboration and license revenue	6,092	(3,178)
Prepaid expenses and other current assets	1,656	(3,253)
Inventories, noncurrent portion	(23,651)	(8,327)
Prepaid and other long-term assets	1,636	5,475
Accounts payable	(2,967)	4,749
Accrued research and development	(4,202)	(28,298)
Accrued and other liabilities	3,114	1,715
Deferred revenue	(875)	(180)
Notes payable, long term royalty-based debt and long-term obligation to collaborator	(8,871)	(316)
Other long-term liabilities	0	(720)
Net cash used in operating activities	(164,585)	(262,677)
Investing activities
Capital expenditures, net	(1,085)	(1,577)
Purchases of investments	(214,534)	(218,330)
Proceeds from maturities of investments	221,231	338,320
Net cash provided by investing activities	5,612	118,413
Financing activities
Proceeds from debt issuance, net	59,203	95,000
Proceeds from issuance of common stock from public offering, net	244,065	0
Proceeds from issuance of common stock pursuant to equity award plans	23,082	14,635
Other	0	(140)
Net cash provided by financing activities	326,350	109,495
Effect of exchange rate changes on cash, cash equivalents and restricted cash	76	0
Net increase (decrease) in cash, cash equivalents and restricted cash	167,453	(34,769)
Cash, cash equivalents and restricted cash at beginning of period	140,013	181,741
Cash, cash equivalents and restricted cash at end of period	$ 307,466	$ 146,972