Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statements of Income (Unaudited) [Abstract]
OPERATING REVENUES	$ 13,048	$ 12,026	$ 24,879	$ 23,670
OPERATING EXPENSES:
Operation and maintenance	2,646	2,563	5,053	4,917
Administrative and general	2,103	2,254	4,009	4,249
Depreciation and amortization	1,933	1,624	3,824	3,465
Taxes other than income taxes	292	267	633	581
Operating expenses	6,974	6,708	13,519	13,212
Operating income	6,074	5,318	11,360	10,458
OTHER INCOME (EXPENSES):
Interest on debt	(1,296)	(1,376)	(2,623)	(2,740)
Allowance for funds used during construction	87	31	156	123
Other pension costs	(363)	(321)	(726)	(642)
Other income (expenses), net	(121)	(77)	(272)	(159)
Other income (expenses)	(1,693)	(1,743)	(3,465)	(3,418)
Income before income taxes	4,381	3,575	7,895	7,040
Income taxes	664	270	1,365	1,141
Net Income	$ 3,717	$ 3,305	$ 6,530	$ 5,899
Basic Earnings Per Share (in dollars per share)	$ 0.28	$ 0.26	$ 0.50	$ 0.46
Diluted Earnings Per Share (in dollars per share)	0.28	0.26	0.50	0.46
Cash Dividends Declared Per Share (in dollars per share)	$ 0.1733	$ 0.1666	$ 0.3466	$ 0.3332