Commitments and Contingencies (Details 5) (USD $)		12 Months Ended						12 Months Ended		1 Months Ended	12 Months Ended	1 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2013 Legal Matters	Sep. 30, 2012 Legal Matters	Sep. 30, 2011 Legal Matters	Sep. 30, 2010 Boynton item	Sep. 30, 2009 Boynton item	Apr. 30, 2011 Boynton	Sep. 30, 2013 AES Thames Bankruptcy	Sep. 30, 2013 Big River	Feb. 29, 2012 Fentress Families Trust item	Sep. 30, 2013 Fentress Families Trust item	Feb. 29, 2012 Neil Wallace	Dec. 31, 2012 CPM	Sep. 30, 2013 Archstone item	Sep. 30, 2008 Archstone item	Sep. 30, 2013 Repair cost Archstone	Sep. 30, 2013 Lost lease payments Archstone	Sep. 30, 2013 Tenant lawsuit against Archstone Archstone	Sep. 30, 2013 Class action defense fees Archstone
Commitments and Contingencies
Long term capital commitments on property, plant and equipment	$ 2,400,000
Legal fees		3,300,000	4,100,000	16,500,000
Potential loss for unresolved matters		16,000,000				43,000,000
Total liability accrued		16,000,000		15,000,000
Verdict for damages					7,300,000	8,700,000
Number of plaintiffs					46	8				383
Constructive trust amount ordered by trial court							16,000,000
Court ordered judgment							16,000,000
Number of defendants										15
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											1
Loss contingency damages sought value								$ 1,600,000	$ 12,400,000			$ 10,000,000	$ 500,000			$ 36,000,000	$ 19,000,000	$ 7,000,000	$ 7,000,000
Number of buildings															21
Number of claims for which summary judgment was sought														3
Number of claims														4
Number of claims dismissed														3