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.

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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- Definition

Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness, attributable to parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e637-108580

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Derivative Instruments and Hedging Activities - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash flow hedges	$ 44,000,000	$ 83,000,000	$ 37,000,000	$ 111,000,000
Interest Rate Swap \| Cash flow hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash flow hedges	43,000,000	$ 78,000,000	39,000,000	$ 105,000,000
Notional amount of derivative	$ 1,000,000,000		$ 1,000,000,000		$ 1,000,000,000
Commodity Contract \| Cash flow hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative					$ 0