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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2012
Asset Retirement Obligation | $ 2.9 | $ 3.2 |
Exposure to Workers Compensation Claims, Per Incident | 1.0 |  |
Discontinued Operations, Receivable from Buyer of Discontinued Operation |  |  | $ 11.8
Workers Compensation Undiscounted Basis Liability | 15.3 | 17.0 |
Workers' Compensation Liability | $ 13.1 | $ 14.7 |
Income Tax Benefit, Likelihood of Realization Threshold | 50.00% |  |
Deferred Finance Costs, Net | $ 8.8 |  |
Minimum [Member] |  |  |
Finite-Lived Tangible Asset, Useful Life, Maximum | 3 years |  |
Debt Instrument, Term | 5 years |  |
Maximum [Member] |  |  |
Finite-Lived Tangible Asset, Useful Life, Maximum | 10 years |  |
Debt Instrument, Term | 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] | Minimum [Member] |  |  |
Property, Plant and Equipment, Useful Life, Minimum | 3 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 | $ 5.6 |  |
Other Current Assets [Member] | U.S. Pipe [Member] |  |  |
Discontinued Operations, Receivable from Buyer of Discontinued Operation | 0.8 |  |
Other Noncurrent Assets [Member] | U.S. Pipe [Member] |  |  |
Discontinued Operations, Receivable from Buyer of Discontinued Operation | 4.3 |  |
ABL Agreement [Member] |  |  |
Deferred Finance Costs, Net | 1.4 |  |
Secured Debt [Member] |  |  |
Deferred Finance Costs, Net | $ 7.4 |  |

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