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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023
Asset Retirement Obligation | $ 4,200,000 |
Exposure to Workers Compensation Claims, Per Incident | 800,000 |
Workers' Compensation Liability | 10,400,000 | $ 9,900,000
Debt Issuance Costs, Net | $ 4,500,000 |
Income Tax Benefit, Likelihood of Realization Threshold | 50.00% |
Minimum [Member] |  |
Finite-Lived Tangible Asset, Useful Life, Maximum | 3 years |
Maximum [Member] |  |
Finite-Lived Tangible Asset, Useful Life, Maximum | 10 years |
Land Improvements [Member] | Minimum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 10 years |
Land Improvements [Member] | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 20 years |
Building [Member] | Minimum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 10 years |
Building [Member] | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 40 years |
Machinery and Equipment [Member] | Minimum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 3 years |
Machinery and Equipment [Member] | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 20 years |
Capitalized internal-use software: | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life, Minimum | 6 years |
U.S. Pipe [Member] | Maximum [Member] |  |
Discontinued Operations, Receivable from Buyer of Discontinued Operation | $ 6,500,000 | 4,600,000
Unsecured Debt [Member] |  |
Debt Issuance Costs, Net | 3,200,000 | $ 3,900,000
Revolving Credit Facility [Member] |  |
Debt Issuance Costs, Net | 1,100,000 |
Debt |  |
Debt Issuance Costs, Net | $ 200,000 |

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