Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Summary Of Significant Accounting Policies [Line Items]
Full cost ceiling test discount factor	10.00%			10.00%
Impairment of Oil and Gas Producing Properties	$ 417,200	$ 588,700	$ 120,300	$ 1,126,257	$ 0	$ 0
Increase (decrease) estimated future net cash flows				194,500	(33,600)	$ 71,600
Goodwill	5,476			5,476	5,476
Prior service (cost) credit	(1,500)			(1,500)	200
Gas stored underground - current	34,252			34,252	39,422
Customer Advances	16,236			16,236	19,005
Customer Security Deposits	16,490			$ 16,490	$ 15,761
Antidilutive securities				709,063	1,007	181,418
Accumulated Losses [Member]
Summary Of Significant Accounting Policies [Line Items]
Accumulated losses	68,300			$ 68,300	$ 56,200
Unamortized Debt Expense [Member]
Summary Of Significant Accounting Policies [Line Items]
Regulated Reacquisition of Debt Cost Weighted Average Amortization Period				4 years
Amount Exceeds LIFO Basis [Member]
Summary Of Significant Accounting Policies [Line Items]
Gas stored underground - current	13,800			$ 13,800
LIFO Method [Member]
Summary Of Significant Accounting Policies [Line Items]
Gas stored underground - current	$ 26,800			26,800
Impairment of Oil and Gas Producing Properties [Member]
Summary Of Significant Accounting Policies [Line Items]
Deferred Income Tax Benefit				$ 476,100