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Debt - Historical Transactions (Details) - USD ($)								12 Months Ended
Debt - Historical Transactions (Details) - USD ($)	Sep. 17, 2024	Jun. 30, 2024	Jun. 29, 2024	Jan. 24, 2024	Jun. 30, 2023	Jan. 27, 2023	Nov. 01, 2022	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Loss on extinguishment of debt								$ 0	$ 4,000,000	$ 0
Acquisition Corp.
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)	1.75%			2.00%
Acquisition Corp. \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)	1.00%			1.00%
Acquisition Corp. \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)	0.50%			0.50%
Acquisition Corp. \| Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)	1.00%			1.00%
Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Term loan borrower alternate base rate election rate								1.00%
Additional interest on overdue principal								2.00%
Acquisition Corp. \| Revolving Credit Facility \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								0.50%
Senior Term Loan Facility
Debt Instrument [Line Items]
Repayments of secured debt								$ 104,000,000	0	0
Senior Term Loan Facility \| Acquisition Corp.
Debt Instrument [Line Items]
Line of credit facility, increase (decrease), net							$ 150,000,000
Line of credit facility, maximum borrowing capacity					$ 1,295,000,000		$ 1,295,000,000
Repayments of secured debt					$ 150,000,000
Loss on extinguishment of debt									4,000,000
Term Loan Mortgage
Debt Instrument [Line Items]
Repayments of secured debt								$ 0	$ 1,000,000	$ 0
Term Loan Mortgage \| Acquisition Corp.
Debt Instrument [Line Items]
Face or principal amount of debt instrument						$ 19,000,000
Term Loan Mortgage \| Acquisition Corp. \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)						1.40%
Initial Revolving Loans \| Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								0.75%
Initial Revolving Loans \| Acquisition Corp. \| Revolving Credit Facility \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								1.75%
2020 Revolving Loans \| Revolving Credit Facility \| Eurodollar Applicable Margin Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)		1.375%	1.875%
2020 Revolving Loans \| Revolving Credit Facility \| ABR Applicable Margin Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)		0.375%	0.875%
2020 Revolving Loans \| Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								0.875%
Senior secured indebtedness to EBITDA ratio								2.05
2020 Revolving Loans \| Acquisition Corp. \| Revolving Credit Facility \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								1.875%
Senior Term Loan Facility -Tranche G \| Acquisition Corp. \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								1.75%
Senior Term Loan Facility -Tranche G \| Acquisition Corp. \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								0.50%
Senior Term Loan Facility -Tranche G \| Acquisition Corp. \| Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percent)								1.00%
Term loan borrower alternate base rate election rate								1.00%
Additional interest rate on other overdue amounts								2.00%