FAIR VALUE MEASUREMENTS: Fair Value, by Balance Sheet Grouping (Details) - USD ($) $ in Thousands		Jun. 30, 2024	Dec. 31, 2023
Corporate Fixed-Income And Asset-Backed Debt Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value		$ 3,400	$ 3,300
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	[1]	3,038	3,038
Held-to-maturity securities	[1],[2]	31,687	31,639
Long-term debt	[1]	2,825,929	2,825,590
Carrying Amount | Idaho Power Company
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	[1],[2]	31,687	31,639
Long-term debt	[1]	2,825,929	2,825,590
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	[1]	3,038	3,038
Held-to-maturity securities	[1],[2]	28,304	28,341
Long-term debt	[1]	2,535,149	2,684,278
Estimated Fair Value | Idaho Power Company
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held-to-maturity securities	[1],[2]	28,304	28,341
Long-term debt	[1]	$ 2,535,149	$ 2,684,278

[1] (1) Notes receivable are categorized as Level 3 and held-to-maturity securities and long-term debt are categorized as Level 2 of the fair value hierarchy, as defined earlier in this Note 12 - "Fair Value Measurements."

[2] (2) All held-to-maturity securities are carried at amortized cost and were in a gross unrealized holding loss position totaling $3.4 million and $3.3 million as of June 30, 2024, and December 31, 2023, respectively. Substantially all of these debt securities mature between 2027 and 2038. Based on ongoing credit evaluations of these holdings, Idaho Power does not expect payment defaults or delinquencies and had not recorded an allowance for credit losses for these securities as of June 30, 2024, and December 31, 2023.