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Debt - Credit Agreement (Details)				12 Months Ended
	Jun. 25, 2021 USD ($)	Apr. 13, 2021 USD ($)	Feb. 08, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Debt agreements
Proceeds from borrowings under credit agreements				$ 3,618,585,000	$ 3,638,916,000	$ 4,452,078,000
Credit Agreement | Base Rate
Debt agreements
Interest rate, basis spread (as a percent)			0.225%
Credit Agreement | LIBOR
Debt agreements
Interest rate, basis spread (as a percent)			1.225%
Credit Agreement | Minimum
Debt agreements
Consolidated leverage ratio			1.00	1.00
Consolidated interest coverage ratio			1.00
Credit Agreement | Maximum
Debt agreements
Consolidated leverage ratio			4.00	2.30
Consolidated interest coverage ratio			3.00
Credit Agreement | Term loan A
Debt agreements
Maximum borrowing capacity			$ 246,968,737.50
Proceeds from borrowings under credit agreements	$ 215,000,000
Credit Agreement | Term B facility
Debt agreements
Maximum borrowing capacity		$ 700,000,000
Credit Agreement | Term B facility | Base Rate
Debt agreements
Interest rate, basis spread (as a percent)		0.75%
Credit Agreement | Term B facility | Euro currency rate
Debt agreements
Interest rate, basis spread (as a percent)		1.75%
Credit Agreement | Revolving credit facility
Debt agreements
Maximum borrowing capacity			$ 1,150,000,000
Current borrowing capacity				$ 1,145,600,000	1,144,800,000
Outstanding letters of credit				$ 4,400,000	$ 5,200,000
2024 Senior Notes
Debt agreements
Interest rate (as a percent)	5.875%	5.875%
2024 Senior Notes | Maximum
Debt agreements
Cash tender offer to purchase		$ 700,000,000

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Face (par) amount of the original debt instrument that was repurchased.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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-Topic 210
-SubTopic 10
-Section S99
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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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Indebtedness divided by net capital.

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