Revenue Recognition from Contracts with Customers (Schedule of Operating Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Regulated Tariff Sales
Residential	$ 16,957	$ 16,681
Commercial	3,576	3,369
Industrial	2,177	2,081
Fire Protection	3,104	3,045
Wholesale	3,539	3,698
Non-Regulated Contract Operations	3,151	2,859
Total Revenue from Contracts with Customers	32,504	31,733
Other Regulated Revenues	68	62
Other Non-Regulated Revenues	106	103
Inter-segment Elimination	(137)	(129)
Total Revenue	$ 32,541	$ 31,769