SCHEDULE I — CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY) - Narrative (Details) $ in Millions	12 Months Ended
Sep. 30, 2021 USD ($)
Guarantee Obligations [Line Items]
Debt repayment in year 2022	$ 110
Debt repayment in year 2023	149
Debt repayment in year 2024	1,356
Debt repayment in year 2025	1,222
Parent Company
Guarantee Obligations [Line Items]
Surety bonds indemnified	75
Maximum amount authorized to guarantee obligations to suppliers and customers (up to)	475
Current carrying value	397
Debt repayment in year 2022	70
Debt repayment in year 2023	38
Debt repayment in year 2024	327
Debt repayment in year 2025	$ 515

Maximum amount authorized to guarantee obligations to suppliers and customers.

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- Definition

Surety bonds indemnified.

+ References

No definition available.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
-Paragraph 3
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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