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Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions |  |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 | Mar. 28, 2024 | Jun. 30, 2021 | Sep. 30, 2025 | Sep. 30, 2024 | May 28, 2021
Debt Instrument [Line Items] |  |  |  |  |  |
Long-Term Debt, Maturity, Year One | $ 1.2 |  |  | $ 1.2 |  |
Long-Term Debt, Maturity, Year Two | 1.2 |  |  | 1.2 |  |
Long-Term Debt, Maturity, Year Three | 1.2 |  |  | 1.2 |  |
Long-Term Debt, Maturity, Year Four | 450.5 |  |  | 450.5 |  |
Outstanding Letter of Credit | 11.1 |  |  | 11.1 |  |
Outstanding Letter Of Credit Accrued Fees And Expenses | 0.2 |  |  | 0.2 |  |
Long-term Debt, Gross | 454.1 |  |  | 454.1 | $ 452.7 |
Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 175.0 |  |  | 175.0 |  |
Line of Credit Facility, Remaining Borrowing Capacity | 163.7 |  |  | 163.7 |  |
Maximum excess availability level at which financial maintenance covenants would apply |  |  |  | 17.5 |  |
Bonds [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  |  |  | 4.00%
Unsecured Debt [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  | 4.00%
Payments of Debt Issuance Costs |  |  | $ 5.5 |  |  |
Long-term Debt, Gross |  |  |  |  |  | $ 450.0
Financial Liabilities Fair Value Disclosure | 434.1 |  |  | $ 434.1 |  |
Debt Instrument, Redemption Price Upon Change In Control, Percentage |  |  |  | 101.00% |  |
Swing Line Loans [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 25.0 |  |  | $ 25.0 |  |
Letter Of Credit [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 60.0 |  |  | 60.0 |  |
Domestic Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Potential Increase In The Size Of Credit Facility |  |  |  | $ 150.0 |  |
Debt Instrument, Basis Spread on Variable Rate |  | 0.10% |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.375% |  |  |  |  |
Line of Credit Facility, Borrowing Base, Percentage of Eligible Accounts Receivable | 85.00% |  |  | 85.00% |  |
Line of Credit Facility, Borrowing Base, Percentage of Eligible Inventory | 70.00% |  |  | 70.00% |  |
Line of Credit Facility, Borrowing Base, Percentage of Net Orderly Liquidation Value of Eligible Inventory | 85.00% |  |  | 85.00% |  |
Line of Credit Facility, Covenant, Percent of Loan Cap | 10.00% |  |  | 10.00% |  |
Debt Instrument, Threshold for Unused Commitment Fee, Percentage of Aggregate Revolving Commitments |  | 50.00% |  |  |  |
Minimum [Member] | Domestic Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage |  | 0.25% |  | 0.375% |  |
Secured Overnight Financing Rate (SOFR) | Domestic Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Interest Rate at Period End | 150.00% |  |  | 150.00% |  |
Secured Overnight Financing Rate (SOFR) | Minimum [Member] | Domestic Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 150.00% |  |  |  |
Secured Overnight Financing Rate (SOFR) | Maximum | Domestic Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 175.00% |  |  |  |
Base Rate [Member] | Domestic Line of Credit |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Line of Credit Facility, Interest Rate at Period End | 50.00% |  |  | 50.00% |  |
Base Rate [Member] | Minimum [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 50.00% |  |  |  |
Base Rate [Member] | Maximum | Revolving Credit Facility [Member] |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 75.00% |  |  |  |

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