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Stock Options and Stock Appreciation Rights - Options (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Apr. 05, 2012
Employee Stock Option |  |  |  |
Stock Options, Aggregate intrinsic value |  |  |  |
Stock-based compensation expense | $ 104,000 | $ 214,000 | $ 330,000 |
Stock-based compensation cost, unrecognized | $ 113,000 |  |  |
Stock-based compensation cost, unrecognized, weighted-average period of recognition | 1 year 2 months 12 days |  |  |
Other information pertaining to option activity |  |  |  |
Total fair value of stock options vested | $ 478,000 | 616,286 | 514,000 |
Total intrinsic value of stock options exercised | $ 1,314,000 | $ 4,640,000 | $ 1,060,000 |
Employee Stock Option | 2012 Plan |  |  |  |
Stock option details |  |  |  |
Shares available for future grants |  |  |  | 800,000
Maximum exercisable period for granted share-based compensation | 10 years |  |  |
Stock option activity |  |  |  |
Options outstanding at the beginning of the period (in shares) | 212,155 |  |  |
Less: |  |  |  |
Options exercised (in shares) | (42,121) |  |  |
Options forfeited (in shares) | (5,150) |  |  |
Options outstanding at the end of the period (in shares) | 164,884 | 212,155 |  |
Options fully vested and exercisable at the end of the period (in shares) | 122,733 |  |  |
Stock Options, Weighted average exercise price |  |  |  |
Options outstanding at the beginning, weighted average exercise price (in dollars per share) | $ 35.27 |  |  |
Less: |  |  |  |
Options exercised, weighted average exercise price (in dollars per share) | 34.81 |  |  |
Options forfeited, weighted average exercise price (in dollars per share) | 34.03 |  |  |
Options outstanding at the end, weighted average exercise price (in dollars per share) | 35.42 | $ 35.27 |  |
Options fully vested and exercisable at the end, weighted average exercise price (in dollars per share) | $ 36.2 |  |  |
Stock Options, Weighted average remaining contractual term (years) |  |  |  |
Options outstanding at the end, weighted average remaining contractual term (years) | 3 years 4 months 13 days |  |  |
Options fully vested and exercisable at the end, weighted average remaining contractual term (years) | 2 years 7 months 24 days |  |  |
Stock Options, Aggregate intrinsic value |  |  |  |
Options outstanding at the end, aggregate intrinsic value | $ 5,115,000 |  |  |
Options fully vested and exercisable at the end, aggregate intrinsic value | $ 3,711,000 |  |  |
Incentive Stock Options to 10 Percent Shareholders | 2012 Plan |  |  |  |
Stock option details |  |  |  |
Maximum exercisable period for granted share-based compensation | 5 years |  |  |

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