General - Revenue Components (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Accounting Policies [Abstract]
Revenue from contracts with customers	$ 207,919	$ 197,777	$ 387,241	$ 362,640
Alternative revenue programs, net	999	1,759	1,261	2,351
Other balancing and memorandum accounts and regulatory mechanisms, net	775	(2,288)	3,651	(988)
Rental income	781	1,007	1,614	1,851
Operating revenue	$ 210,474	$ 198,255	$ 393,767	$ 365,854

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details