Maximum excess availability level at which financial maintenance covenants would apply.

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Maximum excess availability level at which financial maintenance covenants would apply, as a percentage of aggregate commitments.

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No definition available.

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- Definition

Total other amounts reducing excess availability.

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No definition available.

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Potential increase in the size of credit facility.

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No definition available.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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

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No definition available.

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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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Mar. 31, 2019	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 12, 2018
Outstanding letter of credit accrued fees and expenses	$ 15.0
Cash and cash equivalents	220.8		$ 208.9	$ 136.8	$ 176.7
Domestic Line of Credit [Member]
Revolving credit facility amount	$ (175.0)
Line of Credit Facility, Interest Rate at Period End	200.00%
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses	$ 113.4
Future maturities of outstanding borrowings
Line of Credit Facility, Maximum Borrowing Capacity	175.0
Potential increase size of the credit facility by an additional amount	150.0
Aggregate commitments availability	$ 17.5
Aggregate commitments availability, percentage	10.00%
Line of Credit Facility, Remaining Borrowing Capacity	$ 113.4
Unsecured Debt [Member]
Long-term Debt, Gross						$ 450.0
Future maturities of outstanding borrowings
Payments of debt issuance costs		$ 6.6
Swing Line Loans [Member]
Revolving credit facility amount	(25.0)
Future maturities of outstanding borrowings
Line of Credit Facility, Maximum Borrowing Capacity	25.0
Letters Of Credit Outstanding [Member]
Revolving credit facility amount	(60.0)
Future maturities of outstanding borrowings
Line of Credit Facility, Maximum Borrowing Capacity	$ 60.0
5.5% Senior Notes
Debt Instrument, Interest Rate, Effective Percentage	5.50%
Future maturities of outstanding borrowings
Financial Liabilities Fair Value Disclosure	$ 466.3
Minimum [Member] \| Domestic Line of Credit [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	37.50%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Long-term Debt [Member]
Debt Instrument, Basis Spread on Variable Rate	100.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate	200.00%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate	225.00%
Base Rate [Member] \| Maximum [Member] \| Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate	125.00%