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v3.22.2.2

Segment Information (Schedule Of Segment Reporting Information By Segment) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Segment Reporting Information [Line Items] |  |  |  |
Revenues | $ 2,306 | $ 1,811 | $ 5,911 | $ 4,849
Net income (loss) attributable to common shareholders | 452 | 425 | 911 | 865
Capital expenditures | 899 | 850 | 2,437 | 2,613
Wind generation expenditures |  | 98 |  | 515
Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1,359 | 1,129 | 3,096 | 2,642
Net income (loss) attributable to common shareholders | 397 | 375 | 547 | 533
Wind generation expenditures |  | 98 |  | 515
Ameren Illinois Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 904 | 645 | 2,697 | 2,097
Net income (loss) attributable to common shareholders | 103 | 79 | 375 | 314
Capital expenditures | 446 | 380 | 1,145 | 1,026
Operating Segments | Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 1,351 | 1,118 | 3,071 | 2,612
Net income (loss) attributable to common shareholders | 397 | 375 | 547 | 533
Capital expenditures | 431 | 466 | 1,237 | 1,567
Operating Segments | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 672 | 425 | 1,640 | 1,222
Net income (loss) attributable to common shareholders | 51 | 36 | 151 | 123
Capital expenditures | 163 | 143 | 444 | 429
Operating Segments | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 146 | 127 | 811 | 642
Net income (loss) attributable to common shareholders | (4) | (8) | 82 | 75
Capital expenditures | 114 | 93 | 232 | 202
Operating Segments | Ameren Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 137 | 141 | 389 | 373
Net income (loss) attributable to common shareholders | 78 | 73 | 199 | 175
Capital expenditures | 187 | 154 | 519 | 426
Operating Segments | Ameren Illinois Company | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 672 | 428 | 1,641 | 1,227
Net income (loss) attributable to common shareholders | 51 | 36 | 151 | 123
Capital expenditures | 163 | 143 | 444 | 429
Operating Segments | Ameren Illinois Company | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 146 | 127 | 811 | 642
Net income (loss) attributable to common shareholders | (4) | (8) | 82 | 75
Capital expenditures | 114 | 93 | 232 | 202
Operating Segments | Ameren Illinois Company | Ameren Illinois Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 86 | 90 | 245 | 228
Net income (loss) attributable to common shareholders | 56 | 51 | 142 | 116
Capital expenditures | 169 | 144 | 469 | 395
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net income (loss) attributable to common shareholders | (70) | (51) | (68) | (41)
Capital expenditures | 1 | 2 | 4 | 3
Intersegment Eliminations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (40) | (33) | (102) | (88)
Capital expenditures | 3 | (8) | 1 | (14)
Intersegment Eliminations | Union Electric Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (8) | (11) | (25) | (30)
Intersegment Eliminations | Ameren Illinois Electric Distribution |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | 0 | (3) | (1) | (5)
Intersegment Eliminations | Ameren Illinois Natural Gas |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | 0 | 0 | 0 | 0
Intersegment Eliminations | Ameren Transmission |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (32) | (19) | (76) | (53)
Intersegment Eliminations | Ameren Illinois Company |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Intersegment revenues | (31) | (18) | (75) | (49)
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 | $ (31) | $ (18) | $ (75) | $ (49)

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