Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Balances at beginning of period at Dec. 31, 2021	$ 46,258	$ 15	$ 351,394	$ (304,107)	$ (1,044)
Balances at beginning of period (in shares) at Dec. 31, 2021		15,532
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net proceeds from common stock sold	1,333	$ 1	1,332
Common stock sold under agreement | shares		1,073
Issuance of common stock from vesting of restricted stock units (in shares)		594
Tax withholding related to vesting of restricted stock units	(434)		(434)
Issuance of common stock under employee stock purchase plan	37	$ 1	36
Issuance of common stock under employee stock purchase plan (in shares)		27
Stock-based compensation expense	3,668		3,668
Net loss	(18,227)			(18,227)
Foreign currency translation adjustments	79				79
Balances at end of period at Dec. 31, 2022	32,714	$ 17	355,996	(322,334)	(965)
Balances at end of period (in shares) at Dec. 31, 2022		17,226
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from vesting of restricted stock units	1	$ 1
Issuance of common stock from vesting of restricted stock units (in shares)		825
Tax withholding related to vesting of restricted stock units	(238)		(238)
Issuance of common stock under employee stock purchase plan	6		6
Issuance of common stock under employee stock purchase plan (in shares)		13
Stock-based compensation expense	3,105		3,105
Net loss	(21,917)			(21,917)
Foreign currency translation adjustments	(32)				(32)
Balances at end of period at Dec. 31, 2023	$ 13,639	$ 18	$ 358,869	$ (344,251)	$ (997)
Balances at end of period (in shares) at Dec. 31, 2023		18,064