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Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Millions | 1 Months Ended | 12 Months Ended |
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Aug. 31, 2025 director $ / shares shares | Feb. 28, 2025 $ / shares shares | Feb. 29, 2024 $ / shares shares | Feb. 28, 2023 shares | Feb. 28, 2022 shares | Feb. 28, 2014 shares | Sep. 30, 2025 USD ($) shares | Sep. 30, 2024 USD ($) shares | Sep. 30, 2023 USD ($) | Oct. 01, 2023 USD ($)
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Unvested restricted stock outstanding (in shares) |  |  |  |  |  |  | 116,886 | 192,011 |  |
Compensation expense | $ |  |  |  |  |  |  | $ 3.9 | $ 4.2 | $ 4.0 |
Amounts not yet recognized related to non-vested stock totaled | $ |  |  |  |  |  |  | $ 2.4 | 2.1 |  |
Weighted average remaining contractual life |  |  |  |  |  |  | 1 year 4 months 6 days |  |  |
Restricted Stock |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Shares issued annually, grant date value | $ |  |  |  |  |  |  |  |  |  | $ 0.1
Compensation expense | $ |  |  |  |  |  |  | $ 0.7 | $ 0.6 | $ 0.6 |
Weighted average remaining contractual life |  |  |  |  |  |  | 5 months |  |  |
2014 Equity Incentive Plan |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Authorized plan extension period |  |  |  | 5 years |  |  |  |  |  |
Number of additional shares authorized (in shares) |  |  |  | 600,000 |  |  |  |  |  |
Number of shares authorized (in shares) |  |  |  | 1,350,000 |  |  |  |  |  |
2014 Equity Incentive Plan | Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  | 3 years |  |  |  |
2014 Equity Incentive Plan | Restricted Stock Units (RSUs) | Time Based Restricted Stock Unit |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  | 3 years |  |  |  |
2014 Equity Incentive Plan | Restricted Stock Units (RSUs) | Performance Based Restricted Stock Unit |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  | 3 years |  |  |  |
2014 Equity Incentive Plan | Restricted Stock Units (RSUs) | Minimum | Time Based Restricted Stock Unit |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Actual amount of RSUs earned based on cumulative earnings |  |  |  |  |  | 50.00% |  |  |  |
2014 Equity Incentive Plan | Restricted Stock Units (RSUs) | Maximum | Performance Based Restricted Stock Unit |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Target RSUs granted range |  |  |  |  |  | 50.00% |  |  |  |
2014 Director Plan |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Authorized plan extension period |  |  |  |  | 10 years |  |  |  |  |
Number of additional shares authorized (in shares) |  |  |  |  | 200,000 |  |  |  |  |
Number of shares authorized (in shares) |  |  |  |  | 350,000 |  |  |  |  |
Common stock, capital shares reserved for future issuance (in shares) |  |  |  |  |  |  | 182,250 |  |  |
2014 Director Plan | Share-Based Payment Arrangement, Nonemployee |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Number of non-employee directors | director | 1 |  |  |  |  |  |  |  |  |
2014 Director Plan | Restricted Stock |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Unvested restricted stock outstanding (in shares) |  |  |  |  |  |  | 3,730 | 4,620 |  |
Maximum number of shares granted to any individual (in shares) |  |  |  |  |  | 12,000 |  |  |  |
Number of shares issued to any individual (in shares) |  |  |  |  |  | 4,000 |  |  |  |
Restricted stock issuable to eligible Board of Directors members annually (in shares) |  |  |  |  |  | 2,400 |  |  |  |
2014 Director Plan | Restricted Stock | Share-Based Payment Arrangement, Nonemployee |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Shares issued under the plan (in shares) | 230 | 3,500 | 4,620 |  |  |  |  |  |  |
Shares issued, price per share (in dollars per share) | $ / shares | $ 222.25 | $ 200.02 | $ 153.81 |  |  |  |  |  |  |
2014 Director Plan | Restricted Stock | Vesting of First Anniversary |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting percentage |  |  |  |  |  | 50.00% |  |  |  |
2014 Director Plan | Restricted Stock | Vesting of Second Anniversary |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting percentage |  |  |  |  |  | 50.00% |  |  |  |

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