Indebtedness - Schedule of Long Term Debt (Details) - USD ($)	Oct. 31, 2025	Sep. 30, 2025	Oct. 31, 2024	Jun. 30, 2022	Apr. 30, 2019	Jun. 30, 1997
Debt Instrument [Line Items]
Less: unamortized debt issuance costs	$ 2,800,000		$ 2,400,000
Long-term debt	921,500,000		921,800,000
Less: current portion of long-term debt	0		10,000,000.0
Long-term debt, less current portion	921,500,000		911,800,000
Line of Credit | Revolving credit facility, due October 2029
Debt Instrument [Line Items]
Carrying amount of long-term debt	0		0
Senior Notes | Term loan, due October 2029
Debt Instrument [Line Items]
Carrying amount of long-term debt	200,000,000.0		200,000,000.0
Senior Notes | Term loan, due April 2027
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 0		200,000,000.0
Senior Notes | 3.81% series A senior notes, due June 2029
Debt Instrument [Line Items]
Interest rate percentage	3.81%				3.81%
Carrying amount of long-term debt	$ 100,000,000.0		100,000,000.0
Senior Notes | 3.91% series B senior notes, due June 2031
Debt Instrument [Line Items]
Interest rate percentage	3.91%				3.91%
Carrying amount of long-term debt	$ 100,000,000.0		100,000,000.0
Senior Notes | 3.97% senior notes, due June 2032
Debt Instrument [Line Items]
Interest rate percentage	3.97%			3.97%
Carrying amount of long-term debt	$ 100,000,000.0		100,000,000.0
Senior Notes | 5.27% senior notes, due September 2032
Debt Instrument [Line Items]
Interest rate percentage	5.27%	5.27%
Carrying amount of long-term debt	$ 200,000,000.0		0
Senior Notes | 6.625% senior notes, due May 2037
Debt Instrument [Line Items]
Interest rate percentage	6.625%
Carrying amount of long-term debt	$ 124,300,000		124,200,000
Debentures
Debt Instrument [Line Items]
Interest rate percentage						7.80%
Debentures | 7.8% debentures, due June 2027
Debt Instrument [Line Items]
Interest rate percentage	7.80%					7.80%
Carrying amount of long-term debt	$ 100,000,000.0		$ 100,000,000.0
Long-term debt						$ 100,000,000.0