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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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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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-Name Accounting Standards Codification



-Topic 410



-SubTopic 20



-Section 50



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