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v3.25.1

Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Sep. 30, 2024
--- | --- | ---
Debt Instrument [Line Items] |  |
Long-term debt | $ 8,435,000 | $ 7,785,000
Finance lease obligations | 48,075 | 48,890
Total long-term debt | 8,483,075 | 7,833,890
Less: |  |
Original issue premium on unsecured senior notes and debentures | (3,825) | (9,071)
Debt issuance cost | 61,463 | 57,664
Current maturities of long-term debt | 11,712 | 1,651
Total long-term debt, net | $ 8,413,725 | 7,783,646
Unsecured 3.00% Senior Notes, due June 2027 |  |
Debt Instrument [Line Items] |  |
Interest rate | 3.00% |
Long-term debt | $ 500,000 | 500,000
Unsecured 2.625% Senior Notes, due September 2029 |  |
Debt Instrument [Line Items] |  |
Interest rate | 2.625% |
Long-term debt | $ 500,000 | 500,000
Unsecured 1.50% Senior Notes, due January 2031 |  |
Debt Instrument [Line Items] |  |
Interest rate | 1.50% |
Long-term debt | $ 600,000 | 600,000
Unsecured 5.45% Senior Notes, due October 2032 |  |
Debt Instrument [Line Items] |  |
Interest rate | 5.45% |
Long-term debt | $ 300,000 | 300,000
Unsecured 5.90% Senior Notes, due November 2033 |  |
Debt Instrument [Line Items] |  |
Interest rate | 5.90% |
Long-term debt | $ 725,000 | 725,000
Unsecured 5.95% Senior Notes, due October 2034 |  |
Debt Instrument [Line Items] |  |
Interest rate | 5.95% |
Long-term debt | $ 200,000 | 200,000
Unsecured 5.50% Senior Notes, due June 2041 |  |
Debt Instrument [Line Items] |  |
Interest rate | 5.50% |
Long-term debt | $ 400,000 | 400,000
Unsecured 4.15% Senior Notes, due January 2043 |  |
Debt Instrument [Line Items] |  |
Interest rate | 4.15% |
Long-term debt | $ 500,000 | 500,000
Unsecured 4.125% Senior Notes, due October 2044 |  |
Debt Instrument [Line Items] |  |
Interest rate | 4.125% |
Long-term debt | $ 750,000 | 750,000
Unsecured 4.30% Senior Notes, due October 2048 |  |
Debt Instrument [Line Items] |  |
Interest rate | 4.30% |
Long-term debt | $ 600,000 | 600,000
Unsecured 4.125% Senior Notes, due March 2049 |  |
Debt Instrument [Line Items] |  |
Interest rate | 4.125% |
Long-term debt | $ 450,000 | 450,000
Unsecured 3.375% Senior Notes, due September 2049 |  |
Debt Instrument [Line Items] |  |
Interest rate | 3.375% |
Long-term debt | $ 500,000 | 500,000
Unsecured 2.85% Senior Notes, due February 2052 |  |
Debt Instrument [Line Items] |  |
Interest rate | 2.85% |
Long-term debt | $ 600,000 | 600,000
Unsecured 5.75% Senior Notes, due October 2052 |  |
Debt Instrument [Line Items] |  |
Interest rate | 5.75% |
Long-term debt | $ 500,000 | 500,000
Unsecured 6.20% Senior Notes, due November 2053 |  |
Debt Instrument [Line Items] |  |
Interest rate | 6.20% |
Long-term debt | $ 500,000 | 500,000
Unsecured 5.00% Senior Notes, due December 2054 |  |
Debt Instrument [Line Items] |  |
Interest rate | 5.00% |
Long-term debt | $ 650,000 | 0
Medium-term note Series A, 1995-1, 6.67%, due December 2025 |  |
Debt Instrument [Line Items] |  |
Interest rate | 6.67% |
Long-term debt | $ 10,000 | 10,000
Unsecured 6.75% Debentures, due July 2028 |  |
Debt Instrument [Line Items] |  |
Interest rate | 6.75% |
Long-term debt | $ 150,000 | $ 150,000

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