The maximum authorized return on equity, whether requested or approved, in the rate case.

No definition available.

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- Definition

Authorized Return on Equity in Rate Case, Mid-point

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No definition available.

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- Definition

The minimum authorized return on equity, whether requested or approved, in the rate case.

+ References

No definition available.

+ Details

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- Definition

The maximum amount, whether proposed or approved, of additional investment tax credits that are allowed in the rate case in a given year that are computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to investment tax credits generated or utilized under enacted tax laws during the period.

+ References

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The maximum amount, whether proposed or approved, of additional investment tax credits that are allowed in the rate case that are computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to investment tax credits generated or utilized under enacted tax laws during the period.

+ References

No definition available.

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- Definition

[Line Items] for October 2014 Idaho Settlement Stipulation [Table]

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No definition available.

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- Definition

Percentage of earnings to be Shared with Customers, though additional pension expense as a reduction to the pension regulatory asset balancing account, that is above the maximum authorized rate of return in the rate case.

+ References

No definition available.

+ Details

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- Definition

Percentage of earnings to be Shared with Customers, though a rate reduction effective at the time of the subsequent year's power cost adjustment, that is above the maximum authorized rate of return in the rate case.

+ References

No definition available.

+ Details

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- Definition

Percentage of earnings to be Shared with Customers that is above the applicable authorized rate of return in the rate case.

+ References

No definition available.

+ Details

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- Definition

Percentage of earnings to be Shared with the Entity that is above the applicable authorized rate of return in the rate case.

+ References

No definition available.

+ Details

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- Definition

Percentage of target ROE, maximum

+ References

No definition available.

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- Definition

Percentage of target ROE, minimum

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No definition available.

+ Details

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- Definition

The expense charged against earnings during the period to allocate the capitalized costs of regulatory assets over the periods expected to benefit from such costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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-Section 45
-Paragraph 28
-Subparagraph (b)
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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

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No definition available.

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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REGULATORY MATTERS: Idaho Settlement Stipulation (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2020	May 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Apr. 30, 2018	Oct. 31, 2014
Idaho Settlement Stipulation [Line Items]
Regulatory Liabilities			$ 768,834	$ 782,185
October 2014 Idaho Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Authorized Return on Equity in Rate Case, Minimum							9.50%
Investment Tax Credits, Maximum, in Rate Case							$ 45,000
May 2018 Tax Reform Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Authorized Return on Equity in Rate Case, Mid-point							10.00%
Investment Tax Credits, Maximum, in Rate Case			$ 45,000
October 2014 Idaho Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Regulatory Liabilities					$ 5,000
IDAHO \| October 2014 Idaho Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Authorized Return on Equity in Rate Case, Minimum							9.50%
Authorized Return on Equity in Rate Case, Mid-point							10.00%
Authorized Return on Equity in Rate Case, Maximum							10.50%
Investment Tax Credits Maximum In One Year In Rate Case							$ 25,000
Investment Tax Credits, Maximum, in Rate Case							$ 45,000
Percentage to be Shared with Customers							75.00%
Percentage to be Shared with Entity							25.00%
Percent To Be Shared With Customers, Power Cost Adjustment							50.00%
Percent To Be Shared With Customers, Pension Balancing							25.00%
Percentage of target ROE, minimum							95.00%
Percentage of target ROE, maximum							105.00%
IDAHO \| May 2018 Tax Reform Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Authorized Return on Equity in Rate Case, Minimum						9.40%
Authorized Return on Equity in Rate Case, Mid-point						10.00%
Authorized Return on Equity in Rate Case, Maximum						10.50%
Investment Tax Credits Maximum In One Year In Rate Case						$ 25,000
Investment Tax Credits, Maximum, in Rate Case						$ 45,000
Percentage to be Shared with Customers						80.00%
Percentage to be Shared with Entity						20.00%
Percent To Be Shared With Customers, Power Cost Adjustment						55.00%
Percent To Be Shared With Customers, Pension Balancing						25.00%
Percentage of target ROE, minimum						95.00%
Percentage of target ROE, maximum						105.00%
Amortization of Regulatory Asset		$ 7,400
Annual recurring \| IDAHO \| May 2018 Tax Reform Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		18,700
Non-recurring \| IDAHO \| May 2018 Tax Reform Settlement Stipulation
Idaho Settlement Stipulation [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ (2,700)	$ (7,800)