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NDPSC (Details 3) - Pending Rate Case [Member] - Electric - NDPSC [Member] - Montana-Dakota Utilities Co. [Member] - Subsequent Event [Member] $ in Millions | Jul. 17, 2020 USD ($)
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Public Utilities, General Disclosures [Line Items] |
Total Transmission Cost Adjustment Rider | $ 15.5
Public Utilities, Requested Rate Increase (Decrease), Amount | 6.3
Transmission Capital Projects Increase (Decrease) | $ 3.3

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