SEGMENT INFORMATION: Level 4 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Segment Reporting Information
Revenues	$ 253,547	$ 233,924	$ 494,030	$ 484,986
Revenues	254,701	234,983	495,842	486,477
Income (loss) attributable to IDACORP, Inc.	35,438	20,977	60,255	50,465
Income (loss) attributable to IDACORP, Inc.	35,301	20,901	60,230	50,641
Total assets	5,103,003		5,103,003		4,960,609
Idaho Power Company
Segment Reporting Information
Revenues	253,547	233,924	494,030	484,986
Income (loss) attributable to IDACORP, Inc.	34,709	20,701	60,529	50,548
Total assets	4,998,907		4,998,907		4,856,839
Bridger Coal Company
Segment Reporting Information
IERCo's ownership percentage in Bridger Coal Company	33.00%
Idaho Power Company | Idaho Power Company
Segment Reporting Information
Revenues	253,547	233,924	494,030	484,986
Income (loss) attributable to IDACORP, Inc.	34,709	20,701	60,529	50,548
Total assets	4,998,907		4,998,907
All Other
Segment Reporting Information
Revenues	1,154	1,059	1,812	1,491
Income (loss) attributable to IDACORP, Inc.	592	200	(299)	93
Total assets	119,385		119,385
Eliminations
Segment Reporting Information
Revenues	0	0	0	0
Income (loss) attributable to IDACORP, Inc.	0	0	0	0
Total assets	$ (15,289)		$ (15,289)