OTHER INCOME AND EXPENSE Other Income and Expense Level 4 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of other nonoperating income (expense) [Line Items]
Investment Income, net	$ 2,890	$ 2,655	$ 2,373
Carrying charges on regulatory assets	1,774	1,949	2,204
Gain on sale of investments	0	0	11,637
Other Income	777	588	852
Life insurance proceeds, net of premiums	1,739	1,164	18
Other Expense	(21)	(28)	(71)
Other (expense) income, net	7,159	6,328	17,013
Idaho Power Company
Schedule of other nonoperating income (expense) [Line Items]
Investment Income, net	2,889	2,655	2,369
Carrying charges on regulatory assets	1,774	1,949	2,204
Gain on sale of investments	0	0	11,637
Other Income	739	551	700
SMSP expense	(9,937)	(8,339)	(8,488)
Life insurance proceeds, net of premiums	1,739	1,164	18
Other Expense	(2,275)	(2,343)	(2,668)
Other (expense) income, net	$ (5,071)	$ (4,363)	$ 5,772