Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2023	Sep. 30, 2022
Statement of Financial Position [Abstract]
Preferred shares, par value (in usd per share)	$ 0.01	$ 0.01
Preferred shares, authorized (in shares)	10,000,000	10,000,000
Preferred shares, issued (in shares)	0	0
Preferred shares, outstanding (in shares)	0	0
Common shares, par value (in usd per share)	$ 0.01	$ 0.01
Common shares, authorized (in shares)	300,000,000	300,000,000
Common shares, issued (in shares)	65,251,989	65,251,989
Common shares, outstanding (in shares)	50,892,000	51,573,001
Treasury Stock, Common, Shares	14,359,989	13,678,988
Accounts Receivable, Allowance for Credit Loss	$ 6.2	$ 3.8