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NDPSC (Details 2) - Electric - NDPSC [Member] - Montana-Dakota Utilities Co. [Member] - USD ($) | Nov. 01, 2022 | Jul. 14, 2022 | May 16, 2022
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Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities, Interim Rate Increase (Decrease), Amount |  | $ 10,900,000 |
Public Utilities, Interim Rate Increase (Decrease), Percentage |  | 5.30% |
Subsequent Event [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Total Transmission Cost Adjustment Rider | $ 12,900,000 |  |
Public Utilities, Approved Rate Increase (Decrease), Amount | (1,600,000) |  |
Pending Rate Case [Member] |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities, Requested Rate Increase (Decrease), Amount |  |  | $ 25,400,000
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 | (127,000) |  |
Renewable Resource Cost Adjustment Rate Tariff | $ 17,900,000 |  |

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