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v3.19.3.a.u2

Property, Plant, and Equipment | 12 Months Ended
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Dec. 31, 2019
Property, Plant and Equipment [Abstract] |
Property, Plant and Equipment | Property, Plant, and Equipment - MGE Energy and MGE. Property, plant, and equipment consisted of the following as of December 31:
|  |  | MGE Energy |  |  | MGE |
| (In thousands) |  | 2019 |  | 2018 |  |  | 2019 |  | 2018 |
| Utility: |  |  |  |  |  |  |  |  |  |
| Electric(a)(b) | $ | 1,480,684 | $ | 1,310,421 |  | $ | 1,480,701 | $ | 1,310,438 |
| Gas |  | 472,123 |  | 442,581 |  |  | 472,134 |  | 442,593 |
| Total utility plant |  | 1,952,807 |  | 1,753,002 |  |  | 1,952,835 |  | 1,753,031 |
| Less: Accumulated depreciation and amortization(b) |  | 674,251 |  | 639,486 |  |  | 674,251 |  | 639,486 |
| In-service utility plant, net |  | 1,278,556 |  | 1,113,516 |  |  | 1,278,584 |  | 1,113,545 |
| Nonregulated: |  |  |  |  |  |  |  |  |  |
| Nonregulated |  | 323,266 |  | 322,855 |  |  | 323,266 |  | 322,855 |
| Less: Accumulated depreciation and amortization |  | 71,623 |  | 66,605 |  |  | 71,623 |  | 66,605 |
| In-service nonregulated plant, net |  | 251,643 |  | 256,250 |  |  | 251,643 |  | 256,250 |
| Construction work in progress: |  |  |  |  |  |  |  |  |  |
| Utility construction work in progress(a)(b)(c) |  | 111,707 |  | 138,663 |  |  | 111,707 |  | 138,663 |
| Nonregulated construction work in progress |  | 777 |  | 1,008 |  |  | 777 |  | 1,008 |
| Total property, plant, and equipment | $ | 1,642,683 | $ | 1,509,437 |  | $ | 1,642,711 | $ | 1,509,466 |
(a)In December 2017, a one-time tax impact, as a result of the Tax Act, decreased income tax provision and transmission investment $21.7 million and $20.4 million, respectively. (b)Includes long-term debt due within one year, debt issuance costs, and unamortized discount.

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- References No definition available. + Details
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- Definition The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -URI http://asc.fasb.org/topic&trid=2155823 + Details
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