Equity Incentive Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Total shares reserved	49,658,733	46,402,832
Weighted average grant date fair value	$ 2.54	$ 1.97
Fair value of vested options	$ 2.8	$ 5.1
Equity Incentive Plan 2016
Expiration period of share-based payment award	4 years
Shares available for future grants under the 2016 Plan	3,405,908	2,368,160
Maximum \| Equity Incentive Plan 2016
Expiration period of share-based payment award	10 years
Equity Incentive Plan 2016
Percentage of annual increase in number of shares	5.00%
Shares available for future grants under the 2016 Plan	3,405,908
Employee Stock Purchase Plan 2016
Percentage of annual increase in number of shares	1.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	30,000
Additional awards	0
Total shares reserved	11,890
Employee Stock Option
Common stock closing price	$ 1.85
Stock Options And Restricted Stock Awards
Unrecognized compensation cost related to unvested options	$ 2.6
Weighted-average remaining period for recognition of compensation costs related to unvested options	1 year 10 months 24 days
Restricted stock awards \| Minimum
Vesting period of share-based compensation award	2 years
Restricted stock awards \| Maximum
Vesting period of share-based compensation award	4 years

Aggregate number of common shares reserved for future issuance.

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