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Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
	Apr. 05, 2023	Jun. 30, 2021	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2021	Jun. 12, 2018
Outstanding letter of credit accrued fees and expenses			$ 0.1
Cash and cash equivalents				$ 164.1	$ 227.5
Future maturities of outstanding borrowings
Outstanding letters of credit			12.4
Domestic Line of Credit [Member]
Revolving credit facility amount			(175.0)
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
Line of Credit Facility, Borrowing Base, Percentage of Eligible Accounts Receivable			85.00%
Line of Credit Facility, Borrowing Base, Percentage of Eligible Inventory			70.00%
Line of Credit Facility, Borrowing Base, Percentage of Net Orderly Liquidation Value of Eligible Inventory			85.00%
Line of Credit Facility, Covenant, Percent of Loan Cap			10.00%
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			$ 407.9
Debt Instrument, Redemption Price, Percentage			40.00%
Debt Instrument, Redemption Price Upon Change In Control, Percentage			101.00%
Revolving Credit Facility
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses			$ 162.5
Future maturities of outstanding borrowings
Aggregate commitments availability			17.5
Line of Credit Facility, Remaining Borrowing Capacity			$ 162.5
Minimum [Member] | Domestic Line of Credit [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			0.375%
London Interbank Offered Rate (LIBOR) [Member] | Domestic Line of Credit [Member]
Line of Credit Facility, Interest Rate at Period End			2.00%
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate			2.00%
London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate			2.25%
Base Rate [Member] | Domestic Line of Credit [Member]
Line of Credit Facility, Interest Rate at Period End			1.00%
Base Rate [Member] | Minimum [Member] | Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate			1.00%
Base Rate [Member] | Maximum [Member] | Domestic Line of Credit [Member]
Debt Instrument, Basis Spread on Variable Rate			1.25%
Secured Overnight Financing Rate | Domestic Line of Credit [Member] | Subsequent Event [Member]
Debt Instrument, Basis Spread on Variable Rate	0.10%

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