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Stock Options - SARs (Details) - USD ($) |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Apr. 18, 2022 | Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Stock option details |  |  |  |  |  |
Number of rights issued |  |  |  | 8,000 |  |
Base value of units issued (per unit) |  |  |  | $ 53.91 |  |
SARs |  |  |  |  |  |
Outstanding beginning balance |  |  |  | 465,250 |  |
Granted |  |  |  | 8,000 |  |
Forfeited |  |  |  | (11,500) |  |
Outstanding ending balance |  | 461,750 |  | 461,750 |  |
Weighted average exercise price |  |  |  |  |  |
Weighted average exercise price, beginning balance (per share) |  |  |  | $ 39.35 |  |
Weighted average exercise price, granted (per share) |  |  |  | 53.91 |  |
Weighted average exercise price, forfeited (per share) |  |  |  | 39.33 |  |
Weighted average exercise price, ending balance (per share) |  | $ 39.60 |  | $ 39.60 |  |
Aggregate intrinsic value |  |  |  |  |  |
Aggregate intrinsic value |  | $ 8,130,000 |  | $ 8,130,000 |  |
Weighted average remaining contractual term (years) |  |  |  | 8 years 14 days |  |
Stock Appreciation Rights (SARs) |  |  |  |  |  |
Aggregate intrinsic value |  |  |  |  |  |
Fair Value of Liability |  | 2,888,000 |  | $ 2,888,000 |  | $ 1,464,000
Stock-based compensation expense |  | 344,000 | $ 264,000 | 1,424,000 | $ 430,000 |
Stock-based compensation cost, unrecognized |  | $ 7,311,000 |  | $ 7,311,000 |  |
Stock-based compensation cost, unrecognized, weighted-average period of recognition |  |  |  | 8 years |  |
Stock Appreciation Rights (SARs) | SAR Plan |  |  |  |  |  |
Stock option details |  |  |  |  |  |
Shares available for future grants | 750,000 |  |  |  |  |
Maximum exercisable period for granted share-based compensation | 10 years |  |  |  |  |
Number of rights issued |  |  |  | 461,750 |  |
Vesting period | 8 years |  |  |  |  |
SARs |  |  |  |  |  |
Granted |  |  |  | 461,750 |  |

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