Requested Renewable Resource Cost Adjustment Rate Tariff

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

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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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- Definition

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

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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 requested rate increase (decrease) with regulatory agency.

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No definition available.

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- Definition

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

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No definition available.

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Regulatory Matters - NDPSC (Details) - NDPSC - Montana-Dakota Utilities Co. - USD ($) $ in Millions	Jan. 29, 2024	Dec. 13, 2023	Nov. 01, 2023	Oct. 31, 2023
Natural gas distribution \| Pending Rate Case
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount			$ 11.6
Public utilities, requested rate increase (decrease), percentage			7.50%
Public utilities, interim rate increase (decrease), amount		$ 10.1
Public utilities, interim rate increase (decrease), percentage		6.50%
Electric
Public Utilities, General Disclosures [Line Items]
Requested renewable resource cost adjustment rate tariff				$ 21.0
Public utilities, approved rate increase (decrease), amount				$ 4.2
Electric \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Requested renewable resource cost adjustment rate tariff	$ 19.5