The maximum amount of first mortgage bonds issuable.

No definition available.

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- Definition

Debt security and first mortgage bond maximum interest rate limit imposed by the OPUC.

+ References

No definition available.

+ Details

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- Definition

Period of time for maturity if issuing refunding bonds to retire outstanding bonds for which the earnings test does not apply.

+ References

No definition available.

+ Details

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- Definition

The duration of time that the entity is allowed as an extension, as authorized by the respective state regulatory agency, to issue debt.

+ References

No definition available.

+ Details

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- Definition

Amount of additional first mortgage bonds that could be issued under Idaho Power's Indenture of Mortgage and Deed of Trust, as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Percent of operating revenues required to be spent or appropriated for maintenance, retirement, or amortization of properties, as required by the mortgage.

+ References

No definition available.

+ Details

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- Definition

Principal amount of debt securities and first mortgage bonds authorized by the IPUC, OPUC, and WPSC.

+ References

No definition available.

+ Details

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- Definition

Time period expenditures or appropriations can be made up under the terms of the Mortgage agreement.

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period Type:	instant

- Details

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- Details

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LONG-TERM DEBT: Long-term debt narrative Level 4 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	May 19, 2016
Debt Instrument [Line Items]
Repayments of Debt	$ 1,064	$ 101,064	$ 121,064
Idaho Power Company
Debt Instrument [Line Items]
Repayments of Debt	1,064	101,064	121,064
Principal amount of debt securities and first mortgage bonds authorized	$ 500,000
Extension Period of State Regulatory Authorization to Issue Debt	2 years
Debt instrument interest rate limit	7.00%
Debt Instrument, Unused Borrowing Capacity, Amount	$ 500,000
Indenture, Unused Borrowing Capacity, Amount	$ 1,800,000
Percent of Operating Revenues Required to be Spent or Appropriated	15.00%
Time Period Expenditures or Appropriations can be Made Up	5 years
Bonds issuable maximum amount ending	$ 2,500,000			$ 2,000,000
Earnings test does not apply to refunding bonds that mature in less than this period of time	2 years
4.05% Series due 2046
Debt Instrument [Line Items]
First mortgage bonds	$ 120,000	$ 120,000
Debt Instrument, Interest Rate, Stated Percentage	4.05%	4.05%
4.05% Series due 2046 \| Idaho Power Company
Debt Instrument [Line Items]
First mortgage bonds		$ 120,000
Debt Instrument, Interest Rate, Stated Percentage		4.05%
First mortgage bonds 3.65% Series due 2045
Debt Instrument [Line Items]
First mortgage bonds	$ 250,000	$ 250,000
Debt Instrument, Interest Rate, Stated Percentage	3.65%	3.65%
First mortgage bonds 3.65% Series due 2045 \| Idaho Power Company
Debt Instrument [Line Items]
First mortgage bonds			$ 250,000
Debt Instrument, Interest Rate, Stated Percentage			3.65%
First mortgage bonds 6.15 Series due 2019
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		6.15%
Repayments of Debt		$ 100,000
Gains (Losses) on Extinguishment of Debt		$ (14,000)
First mortgage bonds 6.025 Series due 2018 [Member] \| Idaho Power Company
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.025%
Repayments of Debt			$ 120,000
Gains (Losses) on Extinguishment of Debt			$ (17,900)