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v3.25.3

Capitalization and Short-Term Borrowings - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Mar. 06, 2025 | Feb. 19, 2025
Debt Instrument [Line Items] |  |  |  |  |
Total Long-Term Debt |  | $ 2,700,000 | $ 2,700,000 |  |
Less Unamortized Discount and Debt Issuance Costs |  | 17,139 | 11,757 |  |
Less Current Portion | [1] | 300,000 | 500,000 |  |
Long-Term Debt, Net of Current Portion and Unamortized Discount and Debt Issuance Costs |  | 2,382,861 | 2,188,243 |  |
5.20% Notes Due July 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  |  |  | $ 450,000 |
Less Current Portion |  |  | $ 450,000 |  |
Long-term debt, interest rate |  |  | 5.20% | 5.20% |
7.38% due June 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Medium-Term Notes | [2] | $ 0 | $ 50,000 |  |
Less Current Portion |  |  | $ 50,000 |  |
Long-term debt, interest rate |  | 7.38% | 7.38% |  |
2.95% to 5.95% due October 2026 to March 2035 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Notes | [2],[3],[4] | $ 2,400,000 | $ 2,350,000 |  |
Percentage of principal amount |  | 101.00% | 101.00% |  |
2.95% to 5.95% due October 2026 to March 2035 | Minimum |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, interest rate |  | 2.95% | 2.95% |  |
2.95% to 5.95% due October 2026 to March 2035 | Maximum |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, interest rate |  | 5.95% | 5.95% |  |
Term Loan Agreement |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount | [5] | $ 300,000 | $ 300,000 |  |
Less Current Portion |  | $ 300,000 |  |  |
Long-term debt, weighted average variable interest rate |  | 5.62% | 6.71% |  |
Term Loan Agreement | Rate through December 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, variable interest rate |  | 5.43% |  |  |
4.75% Notes Due September 1, 2028 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  | $ 300,000 |  |  |
Long-term debt, interest rate |  | 4.75% |  |  |
Maximum interest rate adjustment |  | 2.00% |  |  |
3.95% Notes Due September 15, 2027 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  | $ 300,000 |  |  |
Long-term debt, interest rate |  | 3.95% |  |  |
Maximum interest rate adjustment |  | 2.00% |  |  |
2.95% Notes Due March 1, 2031 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  | $ 500,000 |  |  |
Long-term debt, interest rate |  | 2.95% |  |  |
Maximum interest rate adjustment |  | 2.00% |  |  |
5.50% Notes Due October 1, 2026 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  | $ 300,000 |  |  |
Long-term debt, interest rate |  | 5.50% |  |  |
Maximum interest rate adjustment |  | 2.00% |  |  |
5.50% Notes Due March 15, 2030 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  | $ 500,000 |  |  | $ 500,000
Long-term debt, interest rate |  | 5.50% |  |  | 5.50%
Maximum interest rate adjustment |  | 2.00% |  |  |
5.50% Notes Due March 15, 2030 | Maximum |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, interest rate |  | 7.50% |  |  |
5.95% Notes Due March 15, 2035 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, face amount |  | $ 500,000 |  |  | $ 500,000
Long-term debt, interest rate |  | 5.95% |  |  | 5.95%
Maximum interest rate adjustment |  | 2.00% |  |  |
5.95% Notes Due March 15, 2035 | Maximum |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term debt, interest rate |  | 7.95% |  |  |
[1] | Current Portion of Long-Term Debt at September 30, 2025 consisted of a $300.0 million long-term delayed draw term loan that matures in February 2026. Current Portion of Long-Term Debt at September 30, 2024 consisted of $50.0 million of 7.38% medium-term notes and $450.0 million of 5.20% notes.
[2] | The Medium-Term Notes and Notes are unsecured.
[3] | The holders of these notes may require the Company to repurchase their notes at a price equal to 101% of the principal amount in the event of both a change in control and a ratings downgrade to a rating below investment grade.
[4] | The interest rate payable on $300.0 million of 4.75% notes, $300.0 million of 3.95% notes, $500.0 million of 2.95% notes and $300.0 million of 5.50% notes will be subject to adjustment from time to time, with a maximum of 2.00%, if certain change of control events involving a material subsidiary result in a downgrade of the credit rating assigned to the notes to below investment grade (or if the credit rating assigned to the notes is subsequently upgraded). The interest rate payable on $500.0 million of 5.50% notes and $500.0 million of 5.95% notes will be subject to adjustment from time to time, with a maximum adjustment of 2.00%, such that the coupon will not exceed 7.50% on the 5.50% notes and 7.95% on the 5.95% notes, if certain change in control events involving a material subsidiary result in a downgrade of the credit rating assigned to the notes to a rating below investment grade. A downgrade with a resulting increase to the coupon does not preclude the coupon from returning to its original rate if the Company’s credit rating is subsequently upgraded.
[5] | The interest rate on the delayed draw term loan, which is based on a weighted average SOFR interest rate, was 5.62% and 6.71% as of September 30, 2025 and September 30, 2024, respectively. The current weighted average locked-in interest rate is 5.43% until mid-December 2025.

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