General - Major Streams of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Accounting Policies [Abstract]
Revenue from contracts with customers	$ 148,657	$ 147,204	$ 270,434	$ 259,442
Alternative revenue programs, net	(2,982)	2,656	(4,909)	2,768
Other balancing and memorandum accounts, net	2,432	1,477	4,862	2,998
Other regulatory mechanisms, net	(432)	(416)	234	(846)
Rental income	1,366	1,320	2,722	2,664
Total revenues	$ 149,041	$ 152,241	$ 273,343	$ 267,026