INCOME TAXES: Level 4 (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Expense [Line Items]
Income tax at statutory rates (federal and state)				$ 27,980	$ 27,590
Excess deferred income tax reversal				(2,962)	(3,262)
Other	[1]			(14,197)	(12,984)
Income Tax Expense		$ 6,933	$ 7,028	$ 10,821	$ 11,344
Effective tax rate				9.90%	10.60%
Idaho Power Company
Income Tax Expense [Line Items]
Income tax at statutory rates (federal and state)				$ 27,613	$ 26,975
Excess deferred income tax reversal				(2,962)	(3,262)
Other	[1]			(13,073)	(11,676)
Income Tax Expense		$ 7,192	$ 7,371	$ 11,578	$ 12,037
Effective tax rate				10.80%	11.50%

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