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v3.23.3

Segment Information (Schedule Of Segment Reporting Information By Segment) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | $ 2,060 | $ 2,306 | $ 5,882 | $ 5,911
Net income (loss) attributable to common shareholders | 493 | 452 | 994 | 911
Capital expenditures | 749 | 899 | 2,571 | 2,437
Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 1,237 | 1,359 | 3,101 | 3,096
Net Income (Loss) | 411 | 397 | 541 | 547
Ameren Illinois Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 783 | 904 | 2,663 | 2,697
Net Income (Loss) | 125 | 103 | 452 | 375
Capital expenditures | 382 | 446 | 1,226 | 1,145
Operating Segments | Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 1,228 | 1,351 | 3,074 | 3,071
Net Income (Loss) | 411 | 397 | 541 | 547
Capital expenditures | 341 | 431 | 1,255 | 1,237
Operating Segments | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 557 | 672 | 1,721 | 1,640
Net Income (Loss) | 66 | 51 | 193 | 151
Capital expenditures | 177 | 163 | 527 | 444
Operating Segments | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 121 | 146 | 664 | 811
Net Income (Loss) | (5) | (4) | 93 | 82
Capital expenditures | 80 | 114 | 221 | 232
Operating Segments | Ameren Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 154 | 137 | 423 | 389
Net Income (Loss) | 86 | 78 | 229 | 199
Capital expenditures | 160 | 187 | 570 | 519
Operating Segments | Ameren Illinois Company | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 558 | 672 | 1,722 | 1,641
Net Income (Loss) | 66 | 51 | 193 | 151
Capital expenditures | 177 | 163 | 527 | 444
Operating Segments | Ameren Illinois Company | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 122 | 146 | 665 | 811
Net Income (Loss) | (5) | (4) | 93 | 82
Capital expenditures | 80 | 114 | 221 | 232
Operating Segments | Ameren Illinois Company | Ameren Illinois Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 103 | 86 | 276 | 245
Net Income (Loss) | 64 | 56 | 166 | 142
Capital expenditures | 125 | 169 | 478 | 469
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net Income (Loss) | (65) | (70) | (62) | (68)
Capital expenditures | 2 | 1 | 7 | 4
Intersegment Eliminations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (45) | (40) | (118) | (102)
Capital expenditures | (11) | 3 | (9) | 1
Intersegment Eliminations | Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (9) | (8) | (27) | (25)
Intersegment Eliminations | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (1) | 0 | (1) | (1)
Intersegment Eliminations | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (1) | 0 | (1) | 0
Intersegment Eliminations | Ameren Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (34) | (32) | (89) | (76)
Intersegment Eliminations | Ameren Illinois Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (33) | (31) | (87) | (75)
Intersegment Eliminations | Ameren Illinois Company | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | 0 | 0 | 0 | 0
Intersegment Eliminations | Ameren Illinois Company | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | 0 | 0 | 0 | 0
Intersegment Eliminations | Ameren Illinois Company | Ameren Illinois Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | $ (33) | $ (31) | $ (87) | $ (75)

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