Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Net operating loss carryforward	$ 37,308	$ 36,136
Stock options and restricted stock	4,528	4,805
Interest expense	258	244
Inventory reserve	410	399
Allowance for doubtful accounts	32	17
Accrued expenses	1,654	1,073
Research and development expense	922	0
Deferred revenue	1,050	880
Leasehold improvements and equipment	60	74
Intangibles	104	95
Operating leases	185	85
Deferred tax assets, gross	46,511	43,808
Less: Valuation allowance	(46,254)	(43,363)
Total deferred tax assets	257	445
Deferred tax liabilities:
Prepaid expenses	(257)	(445)
Total deferred tax liabilities	(257)	(445)
Net deferred tax assets (liabilities)	$ 0	$ 0