CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME Reclassifications out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reclassifications out of Accumulated Other Comprehensive Income before Tax [Abstract]
Reclassification adjustment for gains included in net income, net of tax		$ 0	$ 0	$ 7,087
Reclassifications		2,668	1,728	(5,228)
Accumulated Unrealized Gains and Losses on Available-for-Sale Securities
Reclassifications out of Accumulated Other Comprehensive Income before Tax [Abstract]
Realized gain on sale of securities	[1]	0	0	(11,637)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	[2]	0	0	4,550
Reclassification adjustment for gains included in net income, net of tax		0	0	(7,087)
Reclassifications		0	0	(7,087)
Accumulated Defined Benefit Pension Items
Reclassifications out of Accumulated Other Comprehensive Income before Tax [Abstract]
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	[2]	1,712	1,110	1,192
Amortization of prior service cost	[3]	185	220	212
Amortization of net loss	[3]	4,195	2,618	2,839
Total reclassifications, before tax - pension and postretirement benefits	[3]	4,380	2,838	3,051
Total reclassification, net of tax - pension and postretirement benefits		2,668	1,728	1,859
Reclassifications		$ 2,668	$ 1,728	$ 1,859

[1] The realized gain is included in IDACORP's consolidated income statement in other income, net and in Idaho Power's consolidated income statements in other income (expense), net.

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

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