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Financial Instruments (Tables) | 6 Months Ended
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Mar. 31, 2025
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Schedule of Interest Rate Derivatives | The following table summarizes our existing forward starting interest rate swaps as of March 31, 2025. These swaps were designated as cash flow hedges at the time the agreements were executed.
Planned Debt Issuance Date |  | Amount Hedged |  |
|  | (In thousands) |  |
Fiscal 2026 |  | $ | 300,000 |  |  |
|  | $ | 300,000 |  |  |
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value | The following tables present the fair value and balance sheet classification of our financial instruments as of March 31, 2025 and September 30, 2024. The gross amounts of recognized assets and liabilities are netted within our condensed consolidated balance sheets to the extent that we have netting arrangements with our counterparties. However, as of March 31, 2025 and September 30, 2024, no gross amounts and no cash collateral were netted within our consolidated balance sheet.
|  |  | March 31, 2025
| Balance Sheet Location |  | Assets |  | Liabilities
|  |  | (In thousands)
Designated As Hedges: |  |  |  |  |
Interest rate contracts | Other current assets / Other current liabilities |  | $ | 114,996 |  |  | $ | — |
Total |  |  | 114,996 |  |  | — |
Not Designated As Hedges: |  |  |  |  |
Commodity contracts | Other current assets / Other current liabilities |  | 8,213 |  |  | (561) |
Total |  |  | 8,213 |  |  | (561) |
Gross / Net Financial Instruments |  |  | $ | 123,209 |  |  | $ | (561) |
|  |  | September 30, 2024
| Balance Sheet Location |  | Assets |  | Liabilities
|  |  | (In thousands)
Designated As Hedges: |  |  |  |  |
Interest rate contracts | Deferred charges and other assets / Deferred credits and other liabilities |  | $ | 91,981 |  |  | $ | — |
Total |  |  | 91,981 |  |  | — |
Not Designated As Hedges: |  |  |  |  |
Commodity contracts | Other current assets / Other current liabilities |  | 2,091 |  |  | (7,324) |
Commodity contracts | Deferred charges and other assets / Deferred credits and other liabilities |  | 2,216 |  |  | (313) |
Total |  |  | 4,307 |  |  | (7,637) |
Gross / Net Financial Instruments |  |  | $ | 96,288 |  |  | $ | (7,637) |
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) | The following table summarizes the gains and losses arising from hedging transactions that were recognized as a component of other comprehensive income (loss), net of taxes, for the three and six months ended March 31, 2025 and 2024.
| Three Months Ended March 31 |  | Six Months Ended March 31
| 2025 |  | 2024 |  | 2025 |  | 2024
| (In thousands)
Increase (decrease) in fair value: |  |  |  |  |  |  |
Interest rate agreements | $ | (1,678) |  |  | $ | 29,650 |  |  | $ | 18,041 |  |  | $ | (18,091) |
Recognition of (gains) losses in earnings due to settlements: |  |  |  |  |  |  |
Interest rate agreements | (3,982) |  |  | (2,492) |  |  | (7,140) |  |  | (4,983) |
Total other comprehensive income (loss) from hedging, net of tax | $ | (5,660) |  |  | $ | 27,158 |  |  | $ | 10,901 |  |  | $ | (23,074) |
Schedule of Expected Deferred Gains (Losses) Recognition | The following amounts, net of deferred taxes, represent the expected recognition in earnings of the deferred net gains recorded in AOCI associated with our interest rate agreements, based upon the fair values of these agreements at the date of settlement. The remaining amortization periods for these settled amounts extend through fiscal 2055. However, the table below does not include the expected recognition in earnings of our outstanding interest rate swaps as those instruments have not yet settled.
| Interest Rate Agreements
| (In thousands)
Next twelve months | $ | 15,925 |
Thereafter | 371,080 |
Total | $ | 387,005 |

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