Contingent Liabilities and Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Site Contingency [Line Items]
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]	Other, Other	Other, Other
Environmental Loss Contingency, Current, Statement of Financial Position [Extensible Enumeration]	Other	Other
Environmental Loss Contingency, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other	Other
Regulatory assets	$ 2,054	$ 13,565
Other	10,588	4,011
Environmental assessment and remediation
Site Contingency [Line Items]
Accrual for Environmental Loss Contingencies, Total	1,000	1,000
Accrued environmental assessment and remediation costs, current	200	100
Accrued environmental assessment and remediation costs, noncurrent	800	$ 900
Washington State Climate Commitment Act [Member]
Site Contingency [Line Items]
Regulatory assets	22,300
Other	3,700
Interest Income, affiliate	$ 600