Long-term Debt and Line of Credit - Narrative (Details) - USD ($)		12 Months Ended
	Aug. 09, 2022	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Debt Instrument [Line Items]
Debt issuance cost, gross, noncurrent		$ 900,000	$ 2,200,000
Amortization of debt issuance costs		4,600,000	2,100,000	$ 2,200,000
A&R Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 445,000,000.0
A&R Revolving Facility
Debt Instrument [Line Items]
Letters of credit outstanding, amount		$ 2,800,000	$ 1,600,000
A&R Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	65,000,000.0
Increase in revolving commitment	$ 125,000,000.0
A&R Credit Facility | Minimum
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%
A&R Credit Facility | Maximum
Debt Instrument [Line Items]
Debt instrument, variable interest rate	3.25%
A&R Credit Facility | Swingline Loans
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 5,000,000.0
A&R Credit Facility | Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 5,000,000.0