Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Long term debt	$ 7,960,000
Finance lease obligations (see Note 6)	51,850	$ 18,739
Total long-term debt	8,011,850	7,378,739
Less:
Net original issue discount on unsecured senior notes and debentures	3,704	2,811
Debt issuance cost	46,042	45,271
Current maturities	2,201,457	2,400,452
Long-term debt, noncurrent	$ 5,760,647	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 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	300,000
Unsecured 1.50% Senior Notes, due January 2031
Debt Instrument [Line Items]
Interest rate	1.50%
Long term debt	$ 600,000	600,000
Unsecured 5.95% 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	0
Floating-rate term loan, due April 2022
Debt Instrument [Line Items]
Long term debt	0	200,000
Floating-rate Senior Notes, due March 2023
Debt Instrument [Line Items]
Long term debt	$ 1,100,000	1,100,000
Medium term Series A notes, 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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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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