CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME: Level 4 (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Reclassification out of Accumulated Other Comprehensive Income
Amortization of prior service cost	[1]	$ 42	$ 46
Amortization of net loss	[1]	883	1,049
Total reclassification, before tax - pension and postretirement benefits		925	1,095
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	[2]	(361)	(428)
Total reclassification, net of tax - pension and postretirement benfits		564	667
Reclassifications		564	667
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
AOCI - Beginning Balance		(21,276)	(24,158)
Reclassifications		564	667
AOCI - Ending Balance		(20,712)	(23,491)
Accumulated Defined Benefit Pension Items
Reclassification out of Accumulated Other Comprehensive Income
Reclassifications		564	667
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
AOCI - Beginning Balance		(21,276)	(24,158)
Reclassifications		564	667
AOCI - Ending Balance		$ (20,712)	$ (23,491)

[1] Amortization of these items is included in IDACORP's condensed consolidated income statements in other operating expenses and in Idaho Power's condensed consolidated income statements in other expense, net.

[2] The tax benefit is included in income tax expense in the condensed consolidated income statements of both IDACORP and Idaho Power.