Income Taxes - Schedule of Reconciliations of the U.S. Federal Statutory Tax Rate (Details)	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income Tax Disclosure [Abstract]
U.S. federal statutory rate	21.00%	21.00%	21.00%
State and local taxes, net of U.S. federal tax benefit	0.70%	0.70%	0.50%
Non-U.S. rate differential	0.80%	1.20%	2.60%
Non-U.S. tax holidays	(0.90%)	(1.10%)	(1.20%)
Research and development credits	(0.50%)	(0.50%)	(0.90%)
Foreign derived intangible income	(2.80%)	(2.00%)	(1.60%)
Subsidiary restructuring	0.00%	0.80%	(0.80%)
Russia business exit	0.20%	2.00%	0.00%
Other	3.50%	0.50%	0.00%
Effective income tax rate	22.00%	22.60%	19.60%

Effective Income Tax Rate Reconciliation, Disposition of Business_Russia, Percent

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-12

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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Percentage of reported income tax benefit from difference to income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to foreign-derived intangible income (FDII).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income exempt from income tax because of a tax holiday.

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