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v3.24.3

Segment Information (Schedule Of Segment Reporting Information By Segment) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | $ 2,173 | $ 2,060 | $ 5,682 | $ 5,882
Net income (loss) attributable to common shareholders | 456 | 493 | 975 | 994
Capital expenditures | 1,137 | 749 | 3,029 | 2,571
Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 1,342 | 1,237 | 3,005 | 3,101
Net Income (Loss) | 381 | 411 | 534 | 541
Ameren Illinois Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 793 | 783 | 2,559 | 2,663
Net Income (Loss) | 114 | 125 | 453 | 452
Capital expenditures | 374 | 382 | 1,091 | 1,226
Operating Segments | Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 1,333 | 1,228 | 2,980 | 3,074
Net Income (Loss) | 381 | 411 | 534 | 541
Capital expenditures | 735 | 341 | 1,839 | 1,255
Operating Segments | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 551 | 557 | 1,566 | 1,721
Net Income (Loss) | 56 | 66 | 173 | 193
Capital expenditures | 152 | 177 | 468 | 527
Operating Segments | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 121 | 121 | 660 | 664
Net Income (Loss) | (10) | (5) | 102 | 93
Capital expenditures | 83 | 80 | 202 | 221
Operating Segments | Ameren Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 168 | 154 | 476 | 423
Net Income (Loss) | 90 | 86 | 241 | 229
Capital expenditures | 174 | 160 | 515 | 570
Operating Segments | Ameren Illinois Company | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 552 | 558 | 1,567 | 1,722
Net Income (Loss) | 56 | 66 | 173 | 193
Capital expenditures | 152 | 177 | 468 | 527
Operating Segments | Ameren Illinois Company | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 121 | 122 | 660 | 665
Net Income (Loss) | (10) | (5) | 102 | 93
Capital expenditures | 83 | 80 | 202 | 221
Operating Segments | Ameren Illinois Company | Ameren Illinois Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenues | 120 | 103 | 332 | 276
Net Income (Loss) | 68 | 64 | 178 | 166
Capital expenditures | 139 | 125 | 421 | 478
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net Income (Loss) | (61) | (65) | (75) | (62)
Capital expenditures | 2 | 2 | 6 | 7
Intersegment Eliminations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (52) | (45) | (136) | (118)
Capital expenditures | (9) | (11) | (1) | (9)
Intersegment Eliminations | Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (9) | (9) | (25) | (27)
Intersegment Eliminations | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (1) | (1) | (1) | (1)
Intersegment Eliminations | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | 0 | (1) | 0 | (1)
Intersegment Eliminations | Ameren Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (42) | (34) | (110) | (89)
Intersegment Eliminations | Ameren Illinois Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (35) | (33) | (90) | (87)
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 | $ (35) | $ (33) | $ (90) | $ (87)

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