Minimum threshold percentage that MGEE must hold of the outstanding voting equity interest in MGE.

No definition available.

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- Definition

Disallowable percent ownership of trading stock by an outside party that would result in repurchase of notes at par value.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

+ References

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

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Equity and Financing Arrangements (Details) - USD ($)	3 Months Ended
Equity and Financing Arrangements (Details) - USD ($)	Mar. 31, 2020	Mar. 31, 2019	Apr. 20, 2020
Common Stock [Abstract]
Common stock issued during period	0	0
Dilutive Shares Calculation [Abstract]
Dilutive securities	$ 0
Future Debt Issuance, 2.05%, 2027 Series, Industrial Development Revenue Bonds \| Subsequent Event [Member]
Debt Instrument [Line Items]
Face amount			$ 19,300,000
Interest rate			2.05%
Debt covenant, MGEE's outstanding voting equity interest in MGE			100.00%
Future Debt Issuance, 2.05%, 2027 Series, Industrial Development Revenue Bonds \| Subsequent Event [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt covenant, ownership interest by outside party resulting in repurchase of notes at par value			30.00%
Future Debt Issuance, 2.05%, 2027 Series, Industrial Development Revenue Bonds \| Subsequent Event [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt to total capitalization ratio			0.65
3.45%, 2027 Series, Industrial Development Revenue Bonds
Debt Instrument [Line Items]
Long-term debt, gross	$ 19,300,000