Summary Of Significant Accounting Policies (Schedule Of Property And Equipment) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Allowance for Doubtful Accounts Receivable	$ 0		$ 0		$ 0
Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net	$ 1,327,000	$ 2,449,000	$ 1,823,000	$ 353,000
Building [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life			40 years
Process Equipment - Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life			10 years
Process Equipment - Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life			20 years
Office Equipment - Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life			3 years
Office Equipment - Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life			7 years