EARNINGS PER SHARE: Earnings Per Share Level 4 (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net income attributable to IDACORP, Inc.	$ 232,854	$ 226,801	$ 212,419
Denominator:
Weighted Average Common Shares Outstanding - Basic (in shares)	50,502	50,432	50,361
Effect of Dilutive Securities (in shares)	35	78	63
Weighted Average Common Shares Outstanding - Diluted (in shares)	50,537	50,510	50,424
Earnings Attributable to IDACORP, Inc. - Basic (in dollars per share)	$ 4.61	$ 4.50	$ 4.22
Earnings Attributable to IDACORP, Inc. - Diluted (in dollars per share)	$ 4.61	$ 4.49	$ 4.21