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Stock and Incentive Compensation Plans - Narrative (Details) |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Aug. 01, 2022 shares | Sep. 30, 2025 USD ($) shares | Sep. 30, 2024 USD ($) shares | Sep. 30, 2025 USD ($) category shares | Sep. 30, 2024 USD ($) shares | Apr. 30, 2024 shares
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Stock compensation expense |  | $ 2,268,000 | $ 2,186,000 | $ 6,150,000 | $ 5,953,000 |
BTH | Common Stock |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Stock converted (in shares) | shares | 611,676 |  |  |  |  |
Employee Stock |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Maximum number of common stock available for issuance (in shares) | shares |  | 1,000,000 |  | 1,000,000 |  |
Shares available for issuance (in shares) | shares |  | 812,472 | 871,040 | 812,472 | 871,040 |
Stock repurchase program, discount percentage |  |  |  | 15.00% |  |
Offering period |  |  |  | 1 year |  |
Unrecognized compensation cost |  | $ 337,000 |  | $ 337,000 |  |
Unrecognized compensation cost weighted average period for recognition |  |  |  | 8 months 12 days |  |
Stock compensation expense |  | 127,000 | $ 144,000 | $ 371,000 | $ 369,000 |
PSU |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Unrecognized compensation cost |  | 4,700,000 |  | $ 4,700,000 |  |
Unrecognized compensation cost weighted average period for recognition |  |  |  | 10 months 24 days |  |
Target percentage |  |  |  | 100.00% |  |
Performance period (in years) |  |  |  | 3 years |  |
Expiration period |  |  |  | 3 years |  |
Number of categories | category |  |  |  | 2 |  |
Stock compensation expense |  | 907,000 | 782,000 | $ 2,196,000 | 2,109,000 |
PSU | Minimum |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Target percentage |  |  |  | 0.00% |  |
PSU | Maximum |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Target percentage |  |  |  | 150.00% |  |
RSUs |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Unrecognized compensation cost |  | 10,600,000 |  | $ 10,600,000 |  |
Unrecognized compensation cost weighted average period for recognition |  |  |  | 2 years 9 months 18 days |  |
RSUs | Minimum |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Service period in which time-vested awards are earned |  |  |  | 1 year |  |
RSUs | Maximum |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Service period in which time-vested awards are earned |  |  |  | 7 years |  |
RSAs |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Unrecognized compensation cost |  | 273,000 |  | $ 273,000 |  |
Unrecognized compensation cost weighted average period for recognition |  |  |  | 7 months 6 days |  |
RSAs | Minimum |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Service period in which time-vested awards are earned |  |  |  | 1 year |  |
RSAs | Maximum |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Service period in which time-vested awards are earned |  |  |  | 7 years |  |
Stock Options |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Stock compensation expense |  | $ 0 | $ 0 | $ 0 | $ 0 |
2012 Plan and the Omnibus Plan |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Maximum number of common stock available for issuance (in shares) | shares |  | 1,375,000 |  | 1,375,000 |  |
Omnibus Plan |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Maximum number of common stock available for issuance (in shares) | shares |  | 315,324 |  | 315,324 |  |
Shares available for issuance (in shares) | shares |  |  |  |  |  | 675,000
2012 Plan |  |  |  |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |  |  |  |
Shares available for issuance (in shares) | shares |  |  |  |  |  | 0

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