Rate and Regulatory Matters (Regulatory Framework-Federal) (Details)	12 Months Ended
Dec. 31, 2020
Midwest Independent Transmission System Operator, Inc
Public Utilities, General Disclosures [Line Items]
Incentive adder to FERC allowed base return on common equity	0.50%
FERC revenue requirement reconciliation adjustment
Public Utilities, General Disclosures [Line Items]
Amortization Period	two years

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