Statements of Operations (USD $)	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Statements of Operations [Abstract]
Operating revenues	$ 333,279,000	$ 205,272,000	$ 243,995,000
Operating costs:
Operating expenses	292,519,000	185,588,000	192,839,000
General and administrative	13,550,000	7,131,000	7,856,000
Depreciation	30,536,000	27,126,000	26,160,000
Operating costs total	336,605,000	219,845,000	226,855,000
(Loss) income from operations	(3,326,000)	(14,573,000)	17,140,000
Other income (expense):
Interest income	35,000	185,000	249,000
Interest expense	(167,000)
Other income	651,000	398,000	326,000
(Loss) income before income tax	(2,807,000)	(13,990,000)	17,715,000
Income tax (expense) benefit:
Current	2,929,000	7,102,000	(5,193,000)
Deferred	(3,368,000)	(2,464,000)	(2,300,000)
Income tax (expense) benefit total	(439,000)	4,638,000	(7,493,000)
Net (loss) income	$ (3,246,000)	$ (9,352,000)	$ 10,222,000
Basic (loss) income per common share	$ (0.42)	$ (1.20)	$ 1.31
Diluted (loss) income per common share	$ (0.42)	$ (1.20)	$ 1.30
Weighted average equivalent common shares outstanding	7,809,561	7,777,404	7,807,385
Weighted average equivalent common shares outstanding- assuming dilution	7,809,561	7,777,404	7,853,531