CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Operating Revenues	$ 39,920	$ 37,769	$ 106,965	$ 101,859
Operating Expenses:
Operations and Maintenance	17,949	17,669	52,761	50,569
Depreciation	4,721	4,246	13,798	12,415
Other Taxes	4,073	3,871	11,318	10,913
Total Operating Expenses	26,743	25,786	77,877	73,897
Operating Income	13,177	11,983	29,088	27,962
Other Income (Expense):
Allowance for Funds Used During Construction	953	871	2,871	2,030
Other Income (Expense), net	444	(4)	1,164	(142)
Total Other Income, net	1,397	867	4,035	1,888
Interest Charges	1,906	1,996	5,521	4,984
Income before Income Taxes	12,668	10,854	27,602	24,866
Income Taxes	(69)	(265)	(2,516)	(952)
Net Income	12,737	11,119	30,118	25,818
Preferred Stock Dividend Requirements	30	30	90	102
Earnings Applicable to Common Stock	$ 12,707	$ 11,089	$ 30,028	$ 25,716
Earnings per share of Common Stock:
Basic	$ 0.73	$ 0.67	$ 1.72	$ 1.56
Diluted	$ 0.72	$ 0.66	$ 1.71	$ 1.55
Average Number of Common Shares Outstanding :
Basic	17,466	16,610	17,455	16,520
Diluted	17,581	16,757	17,570	16,673