Consolidated Statements of Income (Unaudited) (USD $)	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Income Statement [Abstract]
Utility operating revenues	$ 9,364,499	$ 8,142,667	$ 14,953,700	$ 13,055,962
Natural gas purchased	3,935,385	3,409,252	5,968,586	5,406,366
Gross margin	5,429,114	4,733,415	8,985,114	7,649,596
Cost and expense
Operating and maintenance expense	1,886,646	1,836,562	3,631,073	2,856,974
Taxes other than income taxes	450,873	494,228	876,948	963,464
Depreciation	563,908	418,841	1,041,232	838,592
Other deductions, net	41,430	30,627	285,166	297,204
Total costs and expenses	2,942,857	2,780,258	5,834,419	4,956,234
Utility operating income	2,486,257	1,953,157	3,150,695	2,693,362
Other income and (expense)
Interest expense	(240,741)	(248,761)	(484,584)	(500,120)
Non-utility expense	(9,435)	(625)	(15,942)	(1,800)
Other income	25,263	24,616	53,105	289,892
Investment income	49,731	48,698	79,458	73,016
Non-utility income from joint venture	21,122		42,719
Rental income	12,138	12,138	24,276	24,276
Net income from operations, before income tax	2,344,335	1,789,223	2,849,727	2,578,626
Income tax benefit (expense), current	(873,815)	(448,274)	(597,879)	(210,843)
Income tax benefit (expense), deferred	33,027	(203,792)	(381,501)	(819,822)
Total tax (expense)	(840,788)	(652,066)	(979,380)	(1,030,665)
Net income	1,503,547	1,137,157	1,870,347	1,547,961
Other comprehensive (loss)
Pension adjustment, net of tax	(94,129)	(106,488)	(188,258)	(304,152)
Net unrealized gain (loss) on securities available for sale	21,722	69,869	5,485	131,355
Total other comprehensive (loss)	(72,407)	(36,619)	(182,773)	(172,797)
Total comprehensive income	$ 1,431,140	$ 1,100,538	$ 1,687,574	$ 1,375,164
Weighted average earnings per share
Basic:	$ 0.67	$ 0.58	$ 0.84	$ 0.82
Diluted:	$ 0.67	$ 0.57	$ 0.83	$ 0.81
Average shares outstanding - basic	2,236,117	1,968,568	2,233,126	1,892,101
Average shares outstanding - diluted	2,245,892	1,981,379	2,243,212	1,905,948