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SDPUC (Details 4) - SDPUC - Montana-Dakota Utilities Co. [Member] - USD ($) | May 01, 2021 | Mar. 11, 2021
--- | --- | ---
Electricity [Member] | Subsequent Event [Member] |  |
Public Utilities, General Disclosures [Line Items] |  |
Total Transmission Cost Adjustment Rider | $ 1,000,000.0 |
Transmission Capital Projects Increase (Decrease) | 274,000 |
Total Infrastructure Rider | 1,000,000.0 |
Public Utilities, Approved Rate Increase (Decrease), Amount | (236,000) |
Gas Distribution [Member] | Subsequent Event [Member] |  |
Public Utilities, General Disclosures [Line Items] |  |
Public Utilities, Approved Rate Increase (Decrease), Amount | $ 5,500,000 |
Pending Rate Case [Member] | Electricity [Member] |  |
Public Utilities, General Disclosures [Line Items] |  |
Total Infrastructure Rider |  | $ 0

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- Definition Total Infrastructure Rider + References No definition available. + Details
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- Definition Total Transmission Cost Adjustment Rider + References No definition available. + Details
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- Definition Transmission Capital Projects Increase (Decrease) + References No definition available. + Details
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- Definition Amount of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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