End date of current fiscal year in the format --MM-DD.

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Maximum Leverage Ratio

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Pro Forma Leverage

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Indebtedness (Narrative) (Details) $ in Millions	12 Months Ended
Indebtedness (Narrative) (Details) $ in Millions	Sep. 30, 2018 USD ($)	Mar. 21, 2018	Mar. 20, 2018
Debt Instrument [Line Items]
Current Fiscal Year End Date	--09-30
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	2.25%	2.00%
Letters of Credit Maximum Issuance Available	$ 75.0
Letters of Credit Outstanding, Amount	31.4
Debt Instrument, Unused Borrowing Capacity, Amount	138.2
Debt Instrument, Periodic Payment, Principal	$ 10.7
Maximum Leverage Ratio		4.5	4.0
Pro Forma Leverage	4.0
Term Loan [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 260.0
Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.25%
Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	0.00%