Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets:
Net operating loss carryforward	$ 35,224	$ 36,735
Stock options and restricted stock	3,849	4,484
Inventory reserve	185	343
Allowance for doubtful accounts	25	18
Accrued expenses	1,746	2,194
Research and development expense	2,507	1,666
Deferred revenue	676	878
Leasehold improvements and equipment	124	99
Intangibles	102	105
Operating leases	238	227
Deferred tax assets, gross	44,676	46,749
Less: Valuation allowance	(44,290)	(46,391)
Total deferred tax assets	386	358
Deferred tax liabilities:
Prepaid expenses	(386)	(358)
Total deferred tax liabilities	(386)	(358)
Net deferred tax assets (liabilities)	$ 0	$ 0