Condensed Consolidated Statement of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net loss	$ (16,495)	$ (10,660)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	286	383
Amortization of bond premium		38
Amortization of operating lease right-of-use assets	294	428
Stock-based compensation expense	2,552	1,308
Change in fair value of derivative instrument		(829)
Gain on sales of marketable securities		(2)
Non-cash interest expense	543	915
Changes in operating assets and liabilities:
Accounts receivable	773	1,065
Prepaid expenses and other assets	(1,476)	(28)
Inventories	(1,534)	(1,426)
Accounts payable	553	1,798
Accrued expenses and other liabilities	502	(978)
Deferred revenue	(161)	27
Operating lease liabilities	(278)	(747)
Net cash used in operating activities	(14,441)	(8,708)
Cash flows from investing activities
Proceeds from maturities of marketable securities		2,750
Purchases and manufacture of property and equipment	(29)	(197)
Net cash provided by investing activities	(29)	2,553
Cash flows from financing activities
Payment of employee restricted stock tax withholdings	(230)
Proceeds from issuance of shares from employee stock purchase plan and stock option exercises		53
Proceeds from issuance of common stock in public offerings, net of offering costs	1,432
Net cash provided by financing activities	1,202	53
Net decrease in cash, cash equivalents and restricted cash	(13,268)	(6,102)
Cash, cash equivalents and restricted cash at beginning of period	23,796	17,344
Cash, cash equivalents and restricted cash at end of period	10,528	11,242
Supplemental disclosures of cash flow information
Cash paid for interest	1,106	928
Supplemental disclosures of noncash activities
Transfer of T2 owned instruments and components (from) to inventory	(271)	(537)
Purchases of property and equipment included in accounts payable and accrued expenses	$ 134	$ 100