Regulatory Matters - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Regulated Asset Liability [Line Items]
Threshold limit of deadband and sharing bands for future surcharge or rebate to customer		$ 4,000
Threshold to return washington energy recovery mechanism dollars to customers		$ 30,000
Proposed cumulative rebate refund period		2 years
Deferred natural gas costs, asset		$ 51,400	$ 52,100
Forecast [Member]
Regulated Asset Liability [Line Items]
Change in energy recovery mechanism over customer	95.00%
Change in energy recovery mechanism over company sharing basis	5.00%
WASHINGTON
Regulated Asset Liability [Line Items]
Decoupling maximum rate increase request		3.00%
WASHINGTON | Power Deferrals Regulatory Asset [Member]
Regulated Asset Liability [Line Items]
Regulatory assets		$ 37,600	30,500
IDAHO | Power Deferrals Regulatory Asset [Member]
Regulated Asset Liability [Line Items]
Regulatory assets		7,600	16,300
Revenue Subject to Refund [Member] | IDAHO
Regulated Asset Liability [Line Items]
Regulatory liabilities		$ 572	$ 686