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v3.22.4

Segment Information (Schedule Of Segment Reporting Information By Segment) (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 USD ($) segment | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Segment Reporting Information [Line Items] |  |  |
Number of reportable segments | segment | 4 |  |
External revenues | $ 7,957 | $ 6,394 | $ 5,794
Depreciation and amortization | 1,289 | 1,146 | 1,075
Interest income | 35 | 27 | 29
Interest Charges | 486 | 383 | 419
Income tax benefit | 176 | 157 | 155
Net Income (Loss) Available to Common Stockholders, Basic | 1,074 | 990 | 871
Capital expenditures | $ 3,351 | 3,479 | 3,233
Wind generation expenditures |  | 525 | 564
Reportable Subsegments |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues |  |  | 5,794
Intersubsegment Eliminations |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues |  |  | 0
Union Electric Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Number of reportable segments | segment | 1 |  |
Ameren Illinois Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Number of reportable segments | segment | 3 |  |
External revenues | $ 3,756 | 2,895 | 2,535
Depreciation and amortization | 514 | 472 | 434
Interest income | 7 | 1 | 3
Interest Charges | 168 | 164 | 155
Income tax benefit | 179 | 143 | 124
Net Income Attributable to Ameren Common Shareholders | 513 | 425 | 379
Capital expenditures | 1,601 | 1,432 | 1,447
Operating Segments | Union Electric Company |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 4,012 | 3,311 | 3,069
Depreciation and amortization | 732 | 632 | 604
Interest income | 28 | 26 | 26
Interest Charges | 213 | 137 | 190
Income tax benefit | (10) | 3 | 34
Net Income Attributable to Ameren Common Shareholders | 562 | 518 | 436
Capital expenditures | 1,690 | 2,015 | 1,666
Operating Segments | Ameren Illinois Electric Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 2,255 | 1,635 | 1,496
Depreciation and amortization | 332 | 309 | 288
Interest income | 7 | 1 | 2
Interest Charges | 74 | 74 | 72
Income tax benefit | 68 | 53 | 42
Net Income Attributable to Ameren Common Shareholders | 202 | 165 | 143
Capital expenditures | 621 | 579 | 543
Operating Segments | Ameren Illinois Gas |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 1,180 | 957 | 760
Depreciation and amortization | 98 | 90 | 81
Interest income | 0 | 0 | 0
Interest Charges | 44 | 42 | 41
Income tax benefit | 46 | 39 | 36
Net Income Attributable to Ameren Common Shareholders | 123 | 108 | 99
Capital expenditures | 308 | 278 | 301
Operating Segments | Ameren Transmission |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 510 | 491 | 469
Depreciation and amortization | 123 | 111 | 98
Interest income | 0 | 0 | 1
Interest Charges | 84 | 83 | 78
Income tax benefit | 92 | 82 | 78
Net Income Attributable to Ameren Common Shareholders | 263 | 230 | 216
Capital expenditures | 741 | 616 | 716
Operating Segments | Ameren Illinois Company | Ameren Illinois Electric Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 2,256 | 1,639 | 1,498
Depreciation and amortization | 332 | 309 | 288
Interest income | 7 | 1 | 2
Interest Charges | 74 | 74 | 72
Income tax benefit | 68 | 53 | 42
Net Income Attributable to Ameren Common Shareholders | 202 | 165 | 143
Capital expenditures | 621 | 579 | 543
Operating Segments | Ameren Illinois Company | Ameren Illinois Gas |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 1,180 | 957 | 760
Depreciation and amortization | 98 | 90 | 81
Interest income | 0 | 0 | 0
Interest Charges | 44 | 42 | 41
Income tax benefit | 46 | 39 | 36
Net Income Attributable to Ameren Common Shareholders | 123 | 108 | 99
Capital expenditures | 308 | 278 | 301
Operating Segments | Ameren Illinois Company | Ameren Illinois Transmission |  |  |
Segment Reporting Information [Line Items] |  |  |
External revenues | 320 | 299 | 277
Depreciation and amortization | 84 | 73 | 65
Interest income | 0 | 0 | 1
Interest Charges | 50 | 48 | 42
Income tax benefit | 65 | 51 | 46
Net Income Attributable to Ameren Common Shareholders | 188 | 152 | 137
Capital expenditures | 672 | 575 | 603
Segment Reconciling Items |  |  |
Segment Reporting Information [Line Items] |  |  |
Depreciation and amortization | 4 | 4 | 4
Interest income | 1 | 3 | 4
Interest Charges | 72 | 50 | 42
Income tax benefit | (20) | (20) | (35)
Net Income Attributable to Ameren Common Shareholders | (76) | (31) | (23)
Capital expenditures | 7 | 4 | 5
Intersegment Elimination |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 140 | 117 | 96
Depreciation and amortization | 0 | 0 | 0
Interest income | (1) | (3) | (4)
Interest Charges | (1) | (3) | (4)
Income tax benefit | 0 | 0 | 0
Capital expenditures | (16) | (13) | 2
Intersegment Elimination | Union Electric Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 34 | 42 | 40
Intersegment Elimination | Ameren Illinois Electric Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 1 | 4 | 2
Intersegment Elimination | Ameren Illinois Gas |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 0 | 0 | 0
Intersegment Elimination | Ameren Transmission |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 105 | 71 | 54
Intersegment Elimination | Ameren Illinois Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 104 | 66 | 52
Intersegment Elimination | Ameren Illinois Company | Ameren Illinois Electric Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 0 | 0 | 0
Intersegment Elimination | Ameren Illinois Company | Ameren Illinois Gas |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | 0 | 0 | 0
Intersegment Elimination | Ameren Illinois Company | Ameren Illinois Transmission |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment revenues | $ 104 | $ 66 | $ 52

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