Annual fixed cost adjustment mechanism deferral amount, whether approved or requested.

No definition available.

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- Definition

Authorized Return on Equity in Rate Case, Mid-point

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Percentage cap on the FCA adjustment.

+ References

No definition available.

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- Definition

Rate Case [Line Items]

+ References

No definition available.

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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to investment tax credit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

No definition available.

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

+ References

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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REGULATORY MATTERS: Level 4 (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	May 31, 2020	May 31, 2019	Jun. 01, 2019	Dec. 31, 2018	Jun. 01, 2018	Apr. 30, 2018	Jun. 01, 2017	Oct. 31, 2014
Regulatory Matters
Revenue from contracts with customers	$ (335,402)	$ (289,573)
Additional accumulated deferred investment tax credits (ADITC) amortization	0	500
Idaho Power Company
Regulatory Matters
Additional accumulated deferred investment tax credits (ADITC) amortization	0	500
Idaho fixed cost adjustment mechanism
Regulatory Matters
Annual fixed cost adjustment mechanism deferral							$ 15,600		$ 35,000
October 2014 Idaho Settlement Stipulation \| IDAHO
Regulatory Matters
Minimum authorized return on equity										9.50%
May 2018 Tax Reform Settlement Stipulation \| IDAHO
Regulatory Matters
Minimum authorized return on equity								9.40%
Target authorized return on equity								10.00%
Settlement Stipulation - Investment Tax Credits and Idaho Sharing Mechanism [Member]
Regulatory Matters
Additional accumulated deferred investment tax credits (ADITC) amortization	0	$ 500
Subsequent event \| Power cost adjustment mechanism
Regulatory Matters
Amount of approved rate change			$ (50,100)	$ (30,400)
Subsequent event \| Idaho fixed cost adjustment mechanism
Regulatory Matters
Amount of approved rate change			19,200	19,400
Annual fixed cost adjustment mechanism deferral					$ 34,800
Percentage cap on the FCA adjustment					3.00%
Subsequent event \| Non-recurring [Member] \| May 2018 Tax Reform Settlement Stipulation \| IDAHO
Regulatory Matters
Amount of approved rate change			(2,700)	$ 7,800
Settlement agreement sharing [Member]
Regulatory Matters
Regulatory liabilities						$ 5,000
Base rate adjustment request for potential Valmy closure [Member] [Member] \| IDAHO
Regulatory Matters
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 1,200
FCAamountexceeding3percentdiscretionarycap [Member] \| Subsequent event \| Idaho fixed cost adjustment mechanism
Regulatory Matters
Amount of approved rate change			$ 4,900