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Revenue (Details-1) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Total Operating Revenue [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | $ 568,855 | $ 559,768 | $ 563,099 | [1]
Electric [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 408,285 | 400,882 | 413,926 |
Electric [Member] | Residential [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 140,006 | 138,566 | 136,168 |
Electric [Member] | Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 213,265 | 204,683 | 216,461 | [1]
Electric [Member] | Industrial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 12,772 | 13,878 | 16,176 |
Electric [Member] | Other-retail/municipal [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 35,174 | 34,023 | 38,010 |
Electric [Member] | Total Retail [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 401,217 | 391,150 | 406,815 |
Electric [Member] | Sales To The Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 5,664 | 7,438 | 4,067 |
Electric [Member] | Other Revenues [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 1,404 | 2,294 | 3,044 |
Gas [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 159,875 | 157,767 | 148,825 |
Gas [Member] | Residential [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 95,146 | 94,017 | 88,695 |
Gas [Member] | Commercial/Industrial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 59,051 | 59,060 | 55,151 | [1]
Gas [Member] | Total Retail [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 154,197 | 153,077 | 143,846 |
Gas [Member] | Gas Transportation [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 5,293 | 4,283 | 4,561 |
Gas [Member] | Other Revenues [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | 385 | 407 | 418 |
Non Regulated Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues recognized from contracts with customers | $ 695 | $ 1,119 | 348 |
MGE [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
CNG Vehicle Fuel Servicing |  |  | $ 100 |
[1] | In 2017, MGE had less than $0.1 million of revenues related to compressed natural gas vehicle fuel servicing. No revenue was recognized for fuel servicing by MGE Energy in 2017.

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