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Equity (Tables) | 9 Months Ended
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Sep. 30, 2023
Schedule of Outstanding, Reserved and Authorized Shares under Share-based Compensation Plans | ​
​ | ​ | ​ | ​ | ​
​ | ​ | September 30, | ​ | December 31,
(in thousands) |  | 2023 |  | 2022
Outstanding options and restricted stock units |  | 3,467 |  | 3,202
Reserved but unissued shares under the Plan | ​ | 2,381 | ​ | 2,777
Total authorized shares under the Plan |  | 5,848 |  | 5,979
Schedule of stock option activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | September 30,
​ | ​ | 2023
(in thousands, except per share data) | ​ | Options to Purchase Common Stock | ​ | Weighted Average Exercise Price | ​ | Weighted Average Remaining Contractual Life (in years)
Outstanding at beginning of year |  | 2,779 | ​ | $ | 2.05 |  | 6.43
Granted |  | — | ​ | $ | — |  | —
Exercised |  | (20) | ​ | $ | 0.54 |  | —
Forfeited/Expired |  | — | ​ | $ | — |  | —
Outstanding at end of period |  | 2,759 | ​ | $ | 2.07 |  | 5.58
Exercisable at end of period |  | 1,991 | ​ | $ | 1.71 |  | 5.00
Schedule of share-based compensation activity | ​
​ | ​ | ​ | ​
​ | ​ | September 30,
(in thousands) |  | 2023
Reserved but unissued shares at beginning of year | ​ | ​ | 196
Increases in the number of authorized shares | ​ | ​ | 5
Grants | ​ | ​ | (12)
Reserved but unissued shares at end of year | ​ |  | 189
Schedule of restricted stock unit activity | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | September 30,
​ | ​ | 2023
(in thousands, except per share data) | ​ | Number of Shares | ​ | Weighted Average Grant Date Fair Value
Nonvested at beginning of year |  | 423 | ​ | $ | 1.49
Granted |  | 538 | ​ | $ | 0.78
Vested |  | (245) | ​ | $ | 1.34
Forfeited | ​ | (8) | ​ | $ | 0.79
Nonvested at end of period |  | 708 | ​ | $ | 1.01
Restricted Stock Units |
Schedule of Compensation Expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Nine Months Ended
​ | ​ | September 30,
(in thousands, except per share data) | ​ | 2023 |  | 2022
Compensation Expense | ​ | $ | 225 | $ | 219 | ​
Weighted Average Value Per Share | ​ | $ | 0.80 | $ | 1.34 | ​
Equity Incentive Plan |
Schedule of Compensation Expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Nine Months Ended
​ | ​ | September 30,
(in thousands, except per share data) |  | 2023 |  | 2022
Fair value | ​ | $ | 234 | ​ | $ | 98
Weighted Average Value Per Share | ​ | $ | 0.79 | ​ | $ | 1.43
Consultant Stock Plan |
Schedule of Compensation Expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Nine Months Ended
​ | ​ | September 30,
(in thousands, except per share data) |  | 2023 |  | 2022
Compensation Expense | ​ | $ | 7 | ​ | $ | 21
Weighted Average Value Per Share | ​ | $ | 0.66 | ​ | $ | 1.93
​

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