EARNINGS PER SHARE: Level 4 (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Numerator:
Net Income Attributable to IDACORP, Inc.	$ 62,288	$ 49,831	$ 98,430	$ 82,933
Denominator:
Weighted-average common shares outstanding - basic	50,435	50,363	50,430	50,361
Effect of dilutive securities	46	44	42	41
Weighted-average common shares outstanding - diluted	50,481	50,407	50,472	50,402
Earnings attributable to IDACORP, Inc. - basic (in dollars per share)	$ 1.24	$ 0.99	$ 1.95	$ 1.65
Earnings attributable to IDACORP, Inc. - diluted (in dollars per share)	$ 1.23	$ 0.99	$ 1.95	$ 1.65