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SDPUC (Details 3) - Pending Rate Case [Member] - SDPUC - Montana-Dakota Utilities Co. [Member] $ in Millions	Aug. 15, 2023 USD ($)
Electric
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 3.0
Public Utilities, Requested Rate Increase (Decrease), Percentage	17.30%
Natural gas distribution
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 7.4
Public Utilities, Requested Rate Increase (Decrease), Percentage	11.20%

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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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