SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES: Level 4 (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	3 Months Ended
Jun. 30, 2012 Marysville Hydro Partners	Jun. 30, 2012 Bridger Coal Company	Jun. 30, 2012 IDACORP Financial Services Limited Partnership Interests
Significant Accounting Policies
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	50.00%	33.00%
Variable interest entities ownership percentage minimum			5.00%
Variable interest entities ownership percentage maximum			99.00%
Variable Interest Entity Ownership Percentage of Partner	50.00%
Variable Interest Entity, Consolidated, Carrying Amount, Assets	$ 20
Variable Interest Entity, Consolidated, Carrying Amount, Assets and Liabilities, Net			57
Variable interest entity consolidated intercompany long term debt	15
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net		102
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 63

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly) - maximum amount of partnership interests.

+ References

No definition available.

+ Details

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly) - minimum amount of partnership interests.

+ References

No definition available.

+ Details

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- Definition

The amount of intercompany long-term debt of the consolidated Variable Interest Entity eliminated in consolidation.

+ References

No definition available.

+ Details

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the partner in the VIE (directly or indirectly).

+ References

No definition available.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=7880789&loc=d3e5710-111685

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The net carrying amount of the consolidated Variable Interest Entity's assets and liabilities included in the reporting entity's statement of financial position.

+ References

No definition available.

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- Definition

Net carrying amount of the assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

+ References

No definition available.

+ Details

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7880789&loc=SL6759159-111685

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