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Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Jan. 14, 2022 | Oct. 01, 2021 | Sep. 30, 2021
--- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |
Long-term debt | $ 7,960,000 |  |  | $ 7,360,000
Finance lease obligations | 52,196 |  |  | 18,739
Total long-term debt | 8,012,196 |  |  | 7,378,739
Less: |  |  |  |
Original issue discount on unsecured senior notes and debentures | 3,760 |  |  | 2,811
Debt issuance cost | 47,842 |  |  | 45,271
Current maturities | 2,201,430 |  |  | 2,400,452
Long-term debt, noncurrent | $ 5,759,164 |  |  | 4,930,205
Unsecured 0.625% Senior Notes, due March 2023 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 0.625% |  |  |
Long-term debt | $ 1,100,000 |  |  | 1,100,000
Unsecured 3.00% Senior Notes, due 2027 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 3.00% |  |  |
Long-term debt | $ 500,000 |  |  | 500,000
Unsecured 2.625% Senior Notes, due 2029 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 2.625% | 2.625% |  |
Long-term debt | $ 500,000 |  |  | 300,000
Unsecured 1.50% Senior Notes, due 2031 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 1.50% |  | 2.85% |
Long-term debt | $ 600,000 |  |  | 600,000
Unsecured 5.95% Senior Notes, due 2034 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 5.95% |  |  |
Long-term debt | $ 200,000 |  |  | 200,000
Unsecured 5.50% Senior Notes, due 2041 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 5.50% |  |  |
Long-term debt | $ 400,000 |  |  | 400,000
Unsecured 4.15% Senior Notes, due 2043 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 4.15% |  |  |
Long-term debt | $ 500,000 |  |  | 500,000
Unsecured 4.125% Senior Notes, due 2044 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 4.125% |  |  |
Long-term debt | $ 750,000 |  |  | 750,000
Unsecured 4.30% Senior Notes, due 2048 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 4.30% |  |  |
Long-term debt | $ 600,000 |  |  | 600,000
Unsecured 4.125% Senior Notes, due 2049 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 4.125% |  |  |
Long-term debt | $ 450,000 |  |  | 450,000
Unsecured 3.375% Senior Notes, due 2049 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 3.375% |  |  |
Long-term debt | $ 500,000 |  |  | 500,000
Unsecured 2.85% Senior Notes, due 2052 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 2.85% |  |  |
Long-term debt | $ 600,000 |  |  | 0
Floating-rate term loan, due April 2022 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | 0 | $ 200,000 |  | 200,000
Floating-rate Senior Notes, due March 2023 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Long-term debt | $ 1,100,000 |  |  | 1,100,000
Medium-term note Series A, 1995-1, 6.67%, due 2025 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 6.67% |  |  |
Long-term debt | $ 10,000 |  |  | 10,000
Unsecured 6.75% Debentures, due 2028 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate | 6.75% |  |  |
Long-term debt | $ 150,000 |  |  | $ 150,000

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