Regulatory Assets and Liabilities - Regulatory Assets (Details-1) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Regulatory Asset [Line Items]
Regulatory Asset	$ 51,637	$ 45,286
Asset Retirement Obligation [Member]
Regulatory Asset [Line Items]
Regulatory Asset	9,592	6,813
Deferred Bad Debt Expense [Member]
Regulatory Asset [Line Items]
Regulatory Asset	2,250	5,200
Debt Related Costs [Member]
Regulatory Asset [Line Items]
Regulatory Asset	6,077	6,538
Derivatives [Member]
Regulatory Asset [Line Items]
Regulatory Asset	1,595	0
Leases [Member]
Regulatory Asset [Line Items]
Regulatory Asset	5,031	4,598
Deferred Pension And Other Postretirement Costs [Member]
Regulatory Asset [Line Items]
Regulatory Asset	0	642
Tax Recovery Related to AFUDC Equity [Member]
Regulatory Asset [Line Items]
Regulatory Asset	14,859	13,440
Electric Transmission Costs [Member]
Regulatory Asset [Line Items]
Regulatory Asset	2,258	1,216
West Riverside Regulatory Asset [Member]
Regulatory Asset [Line Items]
Regulatory Asset	3,453	1,276
Other Regulatory Asset [Member]
Regulatory Asset [Line Items]
Regulatory Asset	$ 6,522	$ 5,563