Regulatory Matters - FERC (Details) - USD ($) $ in Millions	Nov. 16, 2023	Aug. 31, 2023
MISO \| Montana-Dakota Utilities Co. \| Electric
Public Utilities, General Disclosures [Line Items]
Transmission formula revenue requirement	$ 15.4	$ 15.2

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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