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Total other amounts reducing excess availability.

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Outstanding letters of credit

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Potential increase in the size of credit facility.

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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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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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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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Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Sep. 30, 2021	Jun. 12, 2018
Outstanding letter of credit accrued fees and expenses	$ 0.2
Cash and cash equivalents			$ 207.3	$ 227.5
Future maturities of outstanding borrowings
Outstanding letters of credit	12.4
Domestic Line of Credit [Member]
Revolving credit facility amount	$ (175.0)
Line of Credit Facility, Interest Rate at Period End	200.00%
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
Unsecured Debt [Member]
Long-term Debt, Gross					$ 450.0
Future maturities of outstanding borrowings
Payments of debt issuance costs		$ 5.5
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	4.00%
Future maturities of outstanding borrowings
Financial Liabilities Fair Value Disclosure	$ 395.8
Revolving Credit Facility
Future maturities of outstanding borrowings
Aggregate commitments availability	$ 17.5
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%