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Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2023 | Jun. 30, 2021 | Feb. 06, 2024 | Sep. 30, 2023 | May 28, 2021
Long-term Debt, Gross | $ 451.1 |  |  | $ 451.3 |
Outstanding letter of credit accrued fees and expenses | 0.2 |  |  |  |
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
Debt Instrument, Interest Rate, Stated Percentage | 4.00% |  |  |  |
Future maturities of outstanding borrowings |  |  |  |  |
Payments of debt issuance costs |  | $ 5.5 |  |  |
Financial Liabilities Fair Value Disclosure | $ 413.0 |  |  |  |
Debt Instrument, Redemption Price, Percentage | 40.00% |  |  |  |
Debt Instrument, Redemption Price Upon Change In Control, Percentage | 101.00% |  |  |  |
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 |  |  |  |
Revolving Credit Facility |  |  |  |  |
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses | 162.4 |  |  |  |
Future maturities of outstanding borrowings |  |  |  |  |
Aggregate commitments availability | 17.5 |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity | 162.4 |  |  |  |
Revolving Credit Facility, ABL Waiver, Through February 2024 |  |  |  |  |
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses | 50.0 |  |  |  |
Future maturities of outstanding borrowings |  |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity | $ 50.0 |  |  |  |
Revolving Credit Facility, ABL Waiver, Through February 2024 | Subsequent Event [Member] |  |  |  |  |
Excess availability reduced by outstanding borrowings, outstanding letters of credit and accrued fees and expenses |  |  | $ 50.0 |  |
Future maturities of outstanding borrowings |  |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity |  |  | $ 50.0 |  |
Minimum [Member] | Domestic Line of Credit [Member] |  |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.375% |  |  |  |
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] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 0.10% |  |  |  |
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Domestic Line of Credit [Member] |  |  |  |  |
Line of Credit Facility, Interest Rate at Period End | 2.00% |  |  |  |
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Minimum [Member] | Domestic Line of Credit [Member] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 2.00% |  |  |  |
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Maximum [Member] | Domestic Line of Credit [Member] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 2.25% |  |  |  |

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