Commitments and Contingencies (Details 5) (USD $)	12 Months Ended				1 Months Ended		12 Months Ended	1 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2014 Legal Matters	Sep. 30, 2013 Legal Matters	Sep. 30, 2012 Legal Matters	Feb. 28, 2014 Edwards	Feb. 29, 2012 Fentress Families Trust item	Sep. 30, 2010 Fentress Families Trust item	Dec. 31, 2012 CPM Virginia LLC	Sep. 30, 2014 Archstone item	Sep. 30, 2008 Archstone item	Sep. 30, 2014 Repair Cost Archstone	Sep. 30, 2014 Lost Lease Payments Archstone	Sep. 30, 2014 Tenant Lawsuit Against Archstone Archstone	Sep. 30, 2014 Class Action Defense Fees Archstone
Commitments and Contingencies
Long term capital commitments on property, plant and equipment	$ 3,300,000
Legal fees		5,100,000	3,300,000	4,100,000	500,000
Amount accrued for potential losses	2,800,000
Potential loss for unresolved matters		2,800,000
Total liability accrued		2,800,000
Number of plaintiffs						383
Damages for removal and remediation of fly ash and water supply						850,000,000
Damages for vexation						1,900,000,000
Damages for others						8,000,000
Damages for properties plus prejudgment interest, attorney fees and costs						55,000,000
Additional damages sought by other plaintiffs						307,200,000
Number of insurers who have denied coverage							2
Loss contingency damages sought value								$ 500,000			$ 36,000,000	$ 19,000,000	$ 7,000,000	$ 7,000,000
Number of buildings										21
Number of claims									4
Number of claims dismissed									3
Number of defendants						15