CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net (losses) gains on derivative instruments, tax	$ (12)	$ (2)	$ (14)	$ (2)
Reclassifications of net losses on derivative instruments, tax	1	2	3	4
Foreign currency adjustments, tax	(9)	(10)	(13)	2
Benefit plans, tax	$ 0	$ 0	$ (1)	$ 0

Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580

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Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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