Condensed Consolidated Statements of Cash Flows	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (37,640,000)	$ (77,224,000)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation, amortization and accretion	407,000	2,489,000
Amortization of right-of-use assets	903,000
Stock-based compensation expense	5,312,000	5,715,000
(Gain) loss on extinguishment of debt	(3,529,000)	765,000
Gain on sale, abandonment/disposal or impairment of property and equipment		(10,000)
Gain on foreign currency translation	(4,495,000)	(3,107,000)
Interest expense on promissory notes	3,517,000	3,345,000
Write-off of inventory	0	1,792,000
Payment-in-kind interest on promissory notes	(32,822,000)
Other, net	103,000	106,000
Changes in operating assets and liabilities:
Accounts receivable, net	(76,000)	(74,000)
Inventory	(95,000)	(1,920,000)
Prepaid expenses and other current assets	(1,028,000)	(5,000)
Right-of-use and other assets	(356,000)	200,000
Accounts payable	6,282,000	(1,169,000)
Accrued expenses and other current liabilities	(134,000)	560,000
Deferred revenue	(12,721,000)	11,983,000
Recognized loss on purchase commitments	(4,395,000)	(6,165,000)
Operating lease liabilities	(1,064,000)
Accrued interest - promissory notes	(1,545,000)
Net cash used in operating activities	(83,376,000)	(62,719,000)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of limited liability company ownership interest	(300,000)
Proceeds from sale of property and equipment		10,000
Purchase of property and equipment	(2,456,000)
Proceeds from sale of treasury bills	24,995,000
Purchase of treasury bills	(44,880,000)
Net cash used in investing activities	(22,641,000)	10,000
CASH FLOWS FROM FINANCING ACTIVITIES:
Exercise of stock options	50,000
Principal payments on facility financing obligation	(6,920,000)	(2,000,000)
Proceeds of senior convertible notes	9,910,000
Payment of senior convertible notes	(11,081,000)
Proceeds from Midcap credit facility	40,000,000
Issuance cost associated with Midcap credit facility	(886,000)
Proceeds from promissory notes	70,051,000
Issuance cost associated with promissory notes	(33,000)
Principal payments on promissory notes	(38,264,000)
Proceeds from direct placement of common stock		28,000,000
Issuance cost associated with direct placement		(1,610,000)
Payment of employment taxes related to vested restricted stock units		(184,000)
Proceeds from executive stock purchase plan		335,000
Net cash (used) provided by financing activities	64,822,000	25,327,000
NET DECREASE IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	(41,195,000)	(37,382,000)
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH, BEGINNING OF PERIOD	71,684,000	48,355,000
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH, END OF PERIOD	30,489,000	10,973,000
SUPPLEMENTAL CASH FLOWS DISCLOSURES:
Interest paid in cash, net of amounts capitalized		2,895,000
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Property and equipment in progress in accounts payable	203,000
Addition of right-of-use assets upon adoption of new lease guidance	5,192,000
Payment of senior convertible notes through common stock issuance	4,500,000
Principal and interest payments on promissory notes through common stock issuance	8,000,000	8,160,000
Payment of interest on senior convertible notes through common stock issuance	1,075,000
Common stock issuance to settle employee stock purchase plan liability	656,000
Payment of facility obligation through common stock issuance	4,575,000
Payment of note obligations through common stock issuance		42,912,000
Accrued but unpaid debt issuance costs		146,000
At The Market Issuance
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock pursuant to at-the-market offering	2,042,000	819,000
Issuance cost associated with in at-the-market offering	$ (47,000)	$ (33,000)