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v3.23.3

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Product Warranty Expense | $ 14,800,000 | $ 9,500,000 | $ 3,500,000
Asset Retirement Obligation | 4,200,000 |  |
Exposure to Workers Compensation Claims, Per Incident | 800,000 |  |
Workers' Compensation Liability | $ 9,900,000 | $ 11,100,000 |
Income Tax Benefit, Likelihood of Realization Threshold | 50.00% |  |
Debt Issuance Costs, Net | $ 4,600,000 |  |
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 |  |
Software and Software Development Costs [Member] | 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 | $ 4,600,000 | $ 5,900,000 |
Revolving Credit Facility [Member] |  |  |
Debt Issuance Costs, Net | 500,000 |  |
Unsecured Debt [Member] |  |  |
Debt Issuance Costs, Net | 3,900,000 | $ 4,700,000 |
Debt |  |  |
Debt Issuance Costs, Net | $ 200,000 |  |

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