Commitments and Contingencies (Details 2) (USD $)		6 Months Ended				12 Months Ended			6 Months Ended	1 Months Ended	12 Months Ended	1 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended
	Mar. 31, 2014	Mar. 31, 2014 Legal Matters	Mar. 31, 2013 Legal Matters	Sep. 30, 2014 Legal Matters	Sep. 30, 2011 Legal Matters	Sep. 30, 2010 Boynton item	Sep. 30, 2009 Boynton item	Apr. 30, 2011 Boynton	Mar. 31, 2014 AES Thames Bankruptcy	Feb. 29, 2012 Fentress Families Trust item	Sep. 30, 2010 Fentress Families Trust item	Dec. 31, 2012 CPM	Mar. 31, 2014 Archstone item	Sep. 30, 2008 Archstone item	Mar. 31, 2014 Repair cost Archstone	Mar. 31, 2014 Lost lease payments Archstone	Mar. 31, 2014 Tenant lawsuit against Archstone Archstone	Mar. 31, 2014 Class action defense fees Archstone
Commitments and Contingencies
Long term capital commitments on property, plant and equipment	$ 5,300,000
Legal fees		3,900,000	1,100,000
Potential loss for unresolved matters		18,500,000					43,000,000
Total liability accrued		18,500,000		2,500,000	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											2
Loss contingency damages sought value									$ 1,600,000			$ 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