Public Utilities, Requested Rate (Decrease), Net Benefit Amount

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Total Transmission Cost Adjustment Rider

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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.

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Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

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- Definition

Percentage of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

Percentage of public utility's requested return on equity.

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No definition available.

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NDPSC (Details 3) - Electric - NDPSC [Member] - Montana-Dakota Utilities Co. [Member] - USD ($) $ in Millions	Jul. 14, 2023	Apr. 26, 2023	Jul. 14, 2022	May 16, 2022
Public Utilities, General Disclosures [Line Items]
Public Utilities, Interim Rate Increase (Decrease), Amount			$ 10.9
Public Utilities, Interim Rate Increase (Decrease), Percentage			5.30%
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ 15.3
Public Utilities, Requested Rate Increase (Decrease), Amended, Percentage		7.40%
Public Utilities, Requested Return on Equity, Percentage		9.75%
Pending Rate Case [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount				$ 25.4
Public Utilities, Requested Rate Increase (Decrease), Percentage				12.30%
Pending Rate Case [Member] \| Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ (10.7)
Total Transmission Cost Adjustment Rider	2.2
Public Utilities, Requested Rate (Decrease), Net Benefit Amount	$ (7.6)