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v3.19.3.a.u2

Rate Matters (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Oct. 31, 2019 | Oct. 31, 2018 | Oct. 31, 2017 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2017 | Dec. 31, 2018
Tax Cuts and Jobs Act [Member] |  |  |  |  |  |  |
Effects Of The Tax Cuts And Jobs Act [Abstract] |  |  |  |  |  |  |
Return of tax credit |  |  |  |  | $ 3.2 |  | $ 8.2
PSCW [Member] | MGE [Member] |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |
Approved equity capital structure, percentage |  |  |  | 56.10% | 56.60% | 57.20% |
Authorized return on equity, percentage |  |  |  | 9.80% | 9.80% | 9.80% |
Fuel Rules [Abstract] |  |  |  |  |  |  |
Fuel rules, bandwidth |  |  |  |  | 2.00% |  |
Fuel rules, electric fuel costs, deferral, upper threshold |  |  |  |  | 102.00% |  |
Fuel rules, electric fuel costs, deferral, lower threshold |  |  |  |  | 98.00% |  |
Deferred fuel rules monitored costs |  |  |  |  | $ 1.5 |  |
Public Utilities Fuel Surcharge Amount |  |  |  |  | $ 0.5 |  |
Public Utilities Fuel Surcharge Percentage |  |  |  |  | 0.13% |  |
PSCW [Member] | Fuel Rules Refund, 2015/2016 [Member] | MGE [Member] |  |  |  |  |  |  |
Fuel Rules [Abstract] |  |  |  |  |  |  |
Return of electric fuel credit, total |  |  | $ 6.2 |  |  |  |
PSCW [Member] | Fuel Rules Refund, 2017 [Member] | MGE [Member] |  |  |  |  |  |  |
Fuel Rules [Abstract] |  |  |  |  |  |  |
Return of electric fuel credit, total |  | $ 4.2 |  |  |  |  |
PSCW [Member] | Fuel Rules Refund 2018 [Member] | MGE [Member] |  |  |  |  |  |  |
Fuel Rules [Abstract] |  |  |  |  |  |  |
Return of electric fuel credit, total | $ 9.5 |  |  |  |  |  |
Electric Rate Proceeding [Member] | PSCW [Member] | MGE [Member] |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |
Authorized rate increase (decrease), percentage |  |  |  | (0.84%) | (2.24%) | (0.80%) |
Authorized rate increase (decrease), amount |  |  |  | $ (3.4) | $ (9.2) | $ (3.3) |
Gas Rate Proceeding [Member] | PSCW [Member] | MGE [Member] |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |
Authorized rate increase (decrease), percentage |  |  |  | 1.46% | 1.06% | 1.90% |
Authorized rate increase (decrease), amount |  |  |  | $ 2.4 | $ 1.7 | $ 3.1 |

X
- Definition The amount of electric fuel rules monitored costs which have been deferred outside the symmetrical cost tolerance band authorized by a regulatory agency. + References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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- Definition Pursuant to the provisions of the rate order, the fuel rules bandwidth will be plus or minus this percentage. + References No definition available. + Details
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- Definition Under fuel rules, the amount in which an entity is required to defer the benefit of lower costs if actual electric fuel costs were less than the allowed electric fuel costs in latest rate order. + References No definition available. + Details
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- Definition Under fuel rules, the amount in which an entity would defer if actual electric fuel costs exceeded allowed electric fuel costs in latest rate order. + References No definition available. + Details
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- Definition Amount of Public Utility's approved surcharge by regulatory agency. + References No definition available. + Details
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- Definition Percentage of Public Utility's approved surcharge by regulatory agency. + References No definition available. + Details
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- Definition The fuel rules credit that is not required to be refunded to customers and will be amortized. The fuel credit will accrue interest at weighted cost of capital. + References No definition available. + Details
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- Definition The amount of income tax expense over-collection approved by the PSCW for a tax credit to be returned to customers via a bill credit. + References No definition available. + Details
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- Definition Percentage of public utility's approved equity to capital, including debt and equity. + References No definition available. + Details
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- Definition Amount of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
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- Definition Percentage of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
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- Definition Percentage of public utility's approved return on equity. + References No definition available. + Details
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