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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Product Warranty Expense	$ 9,500,000	$ 3,500,000	$ 2,600,000
Asset Retirement Obligation	3,600,000	3,800,000
Exposure to Workers Compensation Claims, Per Incident	800,000
Workers' Compensation Liability	$ 11,100,000	$ 10,500,000
Income Tax Benefit, Likelihood of Realization Threshold	50.00%
Debt Issuance Costs, Net	$ 5,600,000
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	15 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	$ 5,900,000	$ 3,500,000
Revolving Credit Facility [Member]
Debt Issuance Costs, Net	700,000
Secured Debt [Member]
Debt Issuance Costs, Net	4,700,000	$ 5,300,000
Unsecured Debt [Member]
Debt Issuance Costs, Net	4,600,000
Debt
Debt Issuance Costs, Net	$ 300,000

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