Legal, Environmental and Other Contingencies - Overview (Details)	6 Months Ended
	Mar. 31, 2016 action item
Welding rod-related injuries | Pending litigation
Legal, Environmental and Other Contingencies
Number of actions in which the entity is involved | action	2
Asbestos in facilities | Pending litigation
Legal, Environmental and Other Contingencies
Number of actions in which the entity is involved | action	3
Site contingency
Legal, Environmental and Other Contingencies
Number of areas of concern that required investigation | item	1
Number of solid waste management units evaluated under RCRA, as required by IDEM | item	1