INCOME TAXES: Level 4 (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Expense [Line Items]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount				$ 33,722	$ 27,980
Excess deferred income tax reversal				(3,213)	(2,962)
Other	[1]			(14,353)	(14,197)
Income Tax Expense		$ 11,070	$ 6,933	$ 16,156	$ 10,821
Effective tax rate				12.30%	9.90%
Idaho Power Company
Income Tax Expense [Line Items]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount				$ 33,586	$ 27,613
Excess deferred income tax reversal				(3,213)	(2,962)
Other	[1]			(13,082)	(13,073)
Income Tax Expense		$ 11,419	$ 7,192	$ 17,291	$ 11,578
Effective tax rate				13.30%	10.80%

[1] "Other" is primarily comprised of the net tax effect of Idaho Power's regulatory flow-through tax adjustments.