CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net loss	$ (129,455)	$ (141,437)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,091	3,039
Charges (credits) to provision for doubtful accounts	540	(47)
Inventory charge	1,082	5,744
Debt financing fees	4,158	1,645
Share-based compensation	12,779	8,502
Other	726	1,719
Changes in operating assets and liabilities:
Accounts receivable	(5,560)	384
Inventory	(451)	(3,816)
Prepaid and other current assets	(2,831)	2,038
Accounts payable	(1,476)	(3,072)
Accrued expenses and other current liabilities	13,504	(3,813)
Other non-current liabilities	758
Total adjustments	26,320	12,323
Net cash used in operating activities	(103,135)	(129,114)
Cash flows from investing activities:
Payment of patent related costs	(675)	(1,065)
Purchase of fixed assets	(34)	(39)
Net cash used in investing activities	(709)	(1,104)
Cash flows from financing activities:
Proceeds from sale of common stock, net of costs	182,881
Proceeds from exercise of options and warrants	302	272
Proceeds from sale of common stock related to employee stock purchase plan	134
Repayments of debt	(50,000)
Borrowings of debt		50,000
Payment of debt financing fees	(5,118)	(1,250)
Net cash provided by financing activities	128,199	49,022
Net increase (decrease) in cash	24,355	(81,196)
Cash, beginning of period	80,486	160,830
Cash, end of period	104,841	79,634
Supplemental disclosure of noncash financing activities:
Warrants issued in relation to debt financing agreement		7,428
Supplemental disclosure of cash flow information:
Interest paid	$ 19,675	$ 12,032