Revenue (Disaggregation of Revenue) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Total contracts with customers	$ 11,514,422	$ 11,248,650	$ 52,020,432	$ 58,041,904
Revenue reductions (TCJA)			0	(523,881)
Alternative Revenue Programs	(442,504)	434,300	1,274,670	132,752
Operating revenues	11,071,918	11,682,950	53,295,102	58,174,656
Natural Gas [Member] | Residential [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	6,682,586	5,798,846	31,859,828	34,263,845
Natural Gas [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	3,157,873	4,116,695	15,260,652	19,772,433
Natural Gas [Member] | Industrial and Transportation [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	1,401,775	1,098,393	3,972,444	3,563,505
Other [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	272,188	234,716	927,508	966,002
Gas Utility [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	11,298,957	11,100,648	51,483,108	57,497,526
Revenue reductions (TCJA)			0	(523,881)
Alternative Revenue Programs	(442,504)	434,300	1,274,670	132,752
Operating revenues	10,856,453	11,534,948	52,757,778	57,630,278
Gas Utility [Member] | Natural Gas [Member] | Residential [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	6,682,586	5,798,846	31,859,828	34,263,845
Gas Utility [Member] | Natural Gas [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	3,157,873	4,116,695	15,260,652	19,772,433
Gas Utility [Member] | Natural Gas [Member] | Industrial and Transportation [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	1,401,775	1,098,393	3,972,444	3,563,505
Gas Utility [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	56,723	86,714	390,184	421,624
Non Utility [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	215,465	148,002	537,324	544,378
Revenue reductions (TCJA)			0	0
Alternative Revenue Programs	0	0	0	0
Operating revenues	215,465	148,002	537,324	544,378
Non Utility [Member] | Natural Gas [Member] | Residential [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	0	0	0	0
Non Utility [Member] | Natural Gas [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	0	0	0	0
Non Utility [Member] | Natural Gas [Member] | Industrial and Transportation [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	0	0	0	0
Non Utility [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Total contracts with customers	$ 215,465	$ 148,002	$ 537,324	$ 544,378