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v3.21.2

Segment Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | $ 145,873 | $ 135,211 | $ 444,518 | $ 402,124
Equity in earnings of investment |  |  | 7,440 | 7,780
Net income (loss) | 34,917 | 31,794 | 92,701 | 76,622
Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 121,639 | 116,354 | 324,110 | 303,090
Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 24,020 | 18,643 | 119,944 | 98,568
Non Regulated Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 214 | 214 | 464 | 466
Transmission Investment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 0 | 0 | 0 | 0
All Others [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 0 | 0 | 0 | 0
Operating Segments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 145,873 | 135,211 | 444,518 | 402,124
Equity in earnings of investment | 2,532 | 2,353 | 7,440 | 7,780
Operating Segments [Member] | Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 121,728 | 116,563 | 324,426 | 303,674
Equity in earnings of investment | 0 | 0 | 0 | 0
Net income (loss) | 27,833 | 24,761 | 59,979 | 46,439
Operating Segments [Member] | Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 30,709 | 22,137 | 134,321 | 107,868
Equity in earnings of investment | 0 | 0 | 0 | 0
Net income (loss) | (218) | 221 | 11,615 | 9,216
Operating Segments [Member] | Non Regulated Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 10,438 | 10,316 | 31,059 | 30,714
Equity in earnings of investment | 0 | 0 | 0 | 0
Net income (loss) | 5,386 | 5,251 | 15,935 | 15,536
Operating Segments [Member] | Transmission Investment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 0 | 0 | 0 | 0
Equity in earnings of investment | 2,532 | 2,353 | 7,440 | 7,780
Net income (loss) | 1,842 | 1,710 | 5,413 | 5,659
Operating Segments [Member] | All Others [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 0 | 0 | 0 | 0
Equity in earnings of investment | 0 | 0 | 0 | 0
Net income (loss) | 74 | (149) | (241) | (228)
Consolidation Elimination Entries [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | (17,002) | (13,805) | (45,288) | (40,132)
Equity in earnings of investment | 0 | 0 | 0 | 0
Net income (loss) | 0 | 0 | 0 | 0
Consolidation Elimination Entries [Member] | Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 89 | 209 | 316 | 584
Consolidation Elimination Entries [Member] | Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 6,689 | 3,494 | 14,377 | 9,300
Consolidation Elimination Entries [Member] | Non Regulated Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 10,224 | 10,102 | 30,595 | 30,248
Consolidation Elimination Entries [Member] | Transmission Investment [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 0 | 0 | 0 | 0
Consolidation Elimination Entries [Member] | All Others [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 0 | 0 | 0 | 0
MGE [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 145,873 | 135,211 | 444,518 | 402,124
Net income (loss) | 27,374 | 24,740 | 70,774 | 54,437
MGE [Member] | Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 121,639 | 116,354 | 324,110 | 303,090
MGE [Member] | Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 24,020 | 18,643 | 119,944 | 98,568
MGE [Member] | Non Regulated Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 214 | 214 | 464 | 466
MGE [Member] | Operating Segments [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 145,873 | 135,211 | 444,518 | 402,124
Net income (loss) | 27,374 | 24,740 | 70,774 | 54,437
MGE [Member] | Operating Segments [Member] | Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 121,728 | 116,563 | 324,426 | 303,674
Net income (loss) | 27,833 | 24,761 | 59,979 | 46,439
MGE [Member] | Operating Segments [Member] | Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 30,709 | 22,137 | 134,321 | 107,868
Net income (loss) | (218) | 221 | 11,615 | 9,216
MGE [Member] | Operating Segments [Member] | Non Regulated Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 10,438 | 10,316 | 31,059 | 30,714
Net income (loss) | 5,386 | 5,251 | 15,935 | 15,536
MGE [Member] | Consolidation Elimination Entries [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | (17,002) | (13,805) | (45,288) | (40,132)
Net income (loss) | (5,627) | (5,493) | (16,755) | (16,754)
MGE [Member] | Consolidation Elimination Entries [Member] | Electric [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 89 | 209 | 316 | 584
MGE [Member] | Consolidation Elimination Entries [Member] | Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | 6,689 | 3,494 | 14,377 | 9,300
MGE [Member] | Consolidation Elimination Entries [Member] | Non Regulated Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | $ 10,224 | $ 10,102 | $ 30,595 | $ 30,248

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