Credit Agreements - Schedule of Debt Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019	Apr. 03, 2018
Debt Instrument [Line Items]
Principal	$ 825.0	$ 825.0
Debt Issuance Costs, Net	(7.1)	(6.0)
Debt, Net	817.9	819.0
Other short-term debt	5.2
Senior Term Loan
Debt Instrument [Line Items]
Principal	225.0	275.0
Debt Issuance Costs, Net	(0.3)	(0.6)
Debt, Net	224.7	274.4	$ 325.0
4.600% Senior Notes Due May 2028
Debt Instrument [Line Items]
Principal	300.0	300.0
Debt Issuance Costs, Net	(3.0)	(3.4)
Debt, Net	297.0	296.6
3.100% Senior Notes due March 2030
Debt Instrument [Line Items]
Principal	300.0
Debt Issuance Costs, Net	(3.8)
Debt, Net	$ 296.2
5.375% Senior Notes due March 2025
Debt Instrument [Line Items]
Principal		250.0
Debt Issuance Costs, Net		(2.0)
Debt, Net		$ 248.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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