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EMPLOYEE BENEFIT PLANS - Narrative (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jul. 31, 2025 | Sep. 30, 2028 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2026 | Jan. 01, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Defined contribution plan, employer discretionary contribution amount |  |  | $ 12,115 | $ 10,319 | $ 10,857 |  |
Defined contribution plan, employer contributions from excess assets from replacement plan |  |  | 1,525 |  |  |  |
Benefit obligation |  |  | 6,527 |  |  |  |
Other comprehensive income, net |  |  | 4,063 |  |  |  |
Benefit expense |  |  | $ 1,071 |  |  |  |
Cost of benefits annual increase rate (as a percent) |  |  | 7.50% |  |  |  |
Defined benefit plan, period (in years) |  |  | 3 years |  |  |  |
Implementation charges |  |  | $ 1,016 |  |  |  |
Postemployment benefits liability |  |  | $ 1,545 | $ 1,670 |  |  |
Weighted average discount rate |  |  | 5.60% |  |  |  |
Discount rate |  |  | 4.69% | 5.61% | 5.52% |  |
Non-service cost components of net periodic cost (benefit) |  |  | $ (5,411) | $ 137 | $ 866 |  |
Change in discount rate |  |  | 10.00% |  |  |  |
Tax benefit for amortization of pension cost |  |  | $ (402) | $ 578 | 793 |  |
Adjusted funding target attainment percent, threshold |  |  |  |  |  |  | 80.00%
Completion period of service |  |  | 1 year |  |  |  |
Maximum compensation of proportion |  |  | $ 330 |  |  |  |
Allocated shares (in shares) |  |  | 3,977,753 | 4,234,713 |  |  |
Employee stock ownership plan (ESOP), compensation expense |  |  | $ 0 | $ 8,533 | 20,583 |  |
Employee stock ownership plan (ESOP), deferred shares, fair value |  |  |  | $ 1,250 |  |  |
Forecast |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Cost of benefits annual increase rate (as a percent) |  | 6.60% |  |  |  |  |
Implementation charges |  |  |  |  |  | $ 5,362 |
Clopay AMES Plan |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Adjusted funding target attainment percent |  |  |  |  |  |  | 95.00%
Defined benefit plans, estimated future employer catch up contributions in next fiscal year |  |  | 0 |  |  |  |
Hunter Fan Pension Plan |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Defined benefit plans, estimated future employer catch up contributions in next fiscal year |  |  | $ 0 |  |  |  |
Other Postretirement Benefits Plan |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Weighted average discount rate |  |  | 4.87% | 4.08% |  |  |
Total accumulated other comprehensive loss, net of tax |  |  | $ 311 | $ 306 |  |  |
Pension and other postretirement benefit expense |  |  | 19 | 4 | 17 |  |
Pension Plan |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Benefit obligation |  |  | 121,521 | 145,746 | $ 139,224 |  |
Implementation charges |  |  | $ 10,855 | $ 12,959 |  |  |
Weighted average discount rate |  |  | 5.09% | 4.76% |  |  |
Total accumulated other comprehensive loss, net of tax |  |  | $ 22,410 | $ 19,998 |  |  |
Discount rate |  |  | 4.76% | 5.63% | 5.17% |  |
Supplemental Employee Retirement Plan |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Benefit obligation |  |  | $ 10,140 | $ 10,776 | $ 10,882 |  |
Implementation charges |  |  | $ 0 | $ 0 |  |  |
Weighted average discount rate |  |  | 4.52% | 4.46% |  |  |
Total accumulated other comprehensive loss, net of tax |  |  | $ 5,288 | $ 3,663 |  |  |
Discount rate |  |  | 4.46% | 5.53% | 5.02% |  |
Defined benefit plans, estimated future employer contributions in next fiscal year |  |  | $ 1,813 |  |  |  |
Supplemental Employee Retirement Plan | Forecast |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Defined benefit plans, estimated future employer contributions in next fiscal year |  |  |  |  |  | $ 1,567 |
Hunter Fan Pension Plan |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Lump sum distribution for plan termination |  |  | 4,830 |  |  |  |
Plan assets, decrease for assets transferred from plan | $ 6,100 |  | 10,859 |  |  |  |
Defined benefit plan, gain (loss) from plan termination |  |  | $ 2,181 |  |  |  |

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