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Benefit Plans Other Postemployment Benefits (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2024
Other Post-Employment Benefits |  |  |  |
Discount rate | 4.59% | 3.83% | 1.52% |
Period expense | $ (3) | $ (40) | $ (20) |
Postemployment benefits liability, noncurrent | 266 | 299 |  |
Accounts Payable and Accrued Liabilities |  |  |  |
Other Post-Employment Benefits |  |  |  |
Postemployment Benefits Liability, Current | 29 | 29 |  |
Accounts Payable and Accrued Liabilities | Scenario, Forecast |  |  |  |
Other Post-Employment Benefits |  |  |  |
Postemployment Benefits Liability, Current |  |  |  | $ 28
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent |  |  |  |
Other Post-Employment Benefits |  |  |  |
Postemployment benefits liability, noncurrent | $ 237 | $ 270 | $ 340 |

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- Definition The interest rate used to adjust for the time value of money. + References No definition available. + Details
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- Definition For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement that is payable within one year of the balance sheet date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 712 -SubTopic 10 -Name Accounting Standards Codification -Section 25 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481179/712-10-25-4 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 712 -SubTopic 10 -Name Accounting Standards Codification -Section 25 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481179/712-10-25-5 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement that is payable after one year (or beyond the operating cycle if longer). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 712 -SubTopic 10 -Name Accounting Standards Codification -Section 25 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481179/712-10-25-4 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 712 -SubTopic 10 -Name Accounting Standards Codification -Section 25 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481179/712-10-25-5 + Details
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