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SHAREHOLDERS' EQUITY - Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Shares |  |  |  |
Balance at the beginning of the period (in shares) | 447,787 | 617,000 | 701,000 |
Granted (in shares) | 570,000 |  | 95,000 |
Forfeited (in shares) | (67,000) | (159,000) | (159,000) |
Expired (in shares) |  | (10,000) | (20,000) |
Balance at the end of the period (in shares) | 951,170 | 447,787 | 617,000 | 701,000
Exercisable at the end of the period (in shares) | 385,000 |  |  |
Weighted Average Exercise Price |  |  |  |
Balance at the beginning of the period (in dollars per share) | $ 13.43 | $ 13.43 | $ 15.51 |
Granted (in dollars per share) | 7.10 |  | 12.21 |
Proceeds from exercise of stock options |  | $ 4 |  |
Forfeited (in dollars per share) | 11.45 | $ 12.27 | 14.56 |
Expired (in dollars per share) |  | 27.80 | 71.00 |
Balance at the end of the period (in dollars per share) | 9.78 | $ 13.43 | $ 13.43 | $ 15.51
Exercisable (in dollars per share) | $ 13.53 |  |  |
Weighted Average Remaining Contractual Life |  |  |  |
Outstanding at the end of the period | 3 years | 2 years 7 months 6 days | 4 years 2 months 12 days | 4 years 2 months 12 days
Exercisable period of options | 1 year 6 months |  |  |
Intrinsic Value |  |  |  |
Outstanding at the beginning of the period (in dollars) |  | $ 53 | $ 53 |
Exercised (in dollars) |  |  | 10 |
Forfeited (in dollars) | $ 3 | $ 2 | 2 |
Outstanding at the end of the period (in dollars) | $ 61 |  | $ 53 | $ 53
Equity Incentive Plan |  |  |  |
STOCK BASED COMPENSATION |  |  |  |
Number of common stock reserved for issuance | 3,000,000.0 |  |  |
Maximum number of shares that may be subject to grants of options to an individual in a calendar year | 1,000,000 |  |  |
Employees and Directors |  |  |  |
Shares |  |  |  |
Granted (in shares) | 600,000 | 0 | 100,000 |
Weighted Average Exercise Price |  |  |  |
Granted (in dollars per share) | $ 7.1 |  | $ 12.20 |
Intrinsic Value |  |  |  |
Vesting period of options | 3 years |  | 3 years |
Exercise period of options | 5 years |  | 5 years |

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