Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018
Payables And Accruals [Abstract]
Payroll related accruals	$ 43.9	$ 47.4
Accrued operating expenses	63.9	46.5
Other accruals	28.2	24.0
Accrued expenses and other current liabilities	$ 136.0	$ 117.9

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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