Regulatory Matters - Integrated Resource Plan (Details) - Renewable Generation - 2021 Integrated Resource Plan - MPUC [Member]	Jun. 30, 2021 MW
Regulated Operations [Abstract]
Anticipated Additional Generating Capacity (MW)	400
Regulatory Matters [Line Items]
Anticipated Additional Generating Capacity (MW)	400

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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