Segment Information (Disaggregation of Revenue) (Details) - USD ($)
$ in Millions |
3 Months Ended |
6 Months Ended |
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
$ 2,092
|
$ 2,221
|
$ 4,268
|
$ 4,318
|
| Revenues |
2,092
|
2,221
|
4,268
|
4,318
|
| Revenues from alternative revenue programs |
33
|
(14)
|
89
|
4
|
| Other revenues not from contracts with customers |
3
|
4
|
9
|
9
|
| Union Electric Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
0
|
1
|
(3)
|
(4)
|
| Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
26
|
(8)
|
72
|
13
|
| Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
10
|
1
|
27
|
4
|
| Ameren Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
(3)
|
(8)
|
(7)
|
(9)
|
| Electric |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
1,887
|
2,038
|
3,548
|
3,660
|
| Revenues |
1,887
|
2,038
|
3,548
|
3,660
|
| Electric | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
776
|
726
|
1,524
|
1,444
|
| Electric | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
579
|
525
|
1,076
|
978
|
| Electric | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
146
|
132
|
273
|
248
|
| Electric | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
386
|
655
|
675
|
990
|
| Natural gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
205
|
183
|
720
|
658
|
| Revenues |
205
|
183
|
720
|
658
|
| Natural gas | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
129
|
120
|
489
|
472
|
| Natural gas | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
36
|
33
|
142
|
129
|
| Natural gas | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
3
|
4
|
11
|
10
|
| Natural gas | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
37
|
26
|
78
|
47
|
| Ameren Illinois Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
928
|
843
|
2,127
|
1,943
|
| Revenues |
928
|
843
|
2,127
|
1,943
|
| Revenues from alternative revenue programs |
33
|
(14)
|
93
|
9
|
| Other revenues not from contracts with customers |
3
|
6
|
7
|
10
|
| Ameren Illinois Company | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
463
|
428
|
1,124
|
1,079
|
| Ameren Illinois Company | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
227
|
209
|
508
|
466
|
| Ameren Illinois Company | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
54
|
51
|
115
|
105
|
| Ameren Illinois Company | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
184
|
155
|
380
|
293
|
| Ameren Illinois Company | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
26
|
(8)
|
72
|
13
|
| Other revenues not from contracts with customers |
2
|
5
|
5
|
8
|
| Ameren Illinois Company | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
10
|
1
|
27
|
4
|
| Other revenues not from contracts with customers |
1
|
1
|
2
|
2
|
| Ameren Illinois Company | Ameren Illinois Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues from alternative revenue programs |
(3)
|
(7)
|
(6)
|
(8)
|
| Other revenues not from contracts with customers |
0
|
0
|
0
|
0
|
| Ameren Illinois Company | Electric |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
752
|
685
|
1,515
|
1,374
|
| Ameren Illinois Company | Natural gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
176
|
158
|
612
|
569
|
| Operating Segments | Union Electric Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
1,111
|
1,332
|
2,031
|
2,282
|
| Revenues |
1,124
|
1,340
|
2,054
|
2,297
|
| Other revenues not from contracts with customers |
2
|
2
|
4
|
3
|
| Operating Segments | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
629
|
570
|
1,272
|
1,140
|
| Revenues |
629
|
573
|
1,272
|
1,145
|
| Other revenues not from contracts with customers |
2
|
5
|
5
|
8
|
| Operating Segments | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
176
|
158
|
612
|
569
|
| Revenues |
176
|
158
|
612
|
569
|
| Other revenues not from contracts with customers |
1
|
1
|
2
|
2
|
| Operating Segments | Ameren Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
176
|
161
|
353
|
327
|
| Revenues |
229
|
208
|
456
|
418
|
| Other revenues not from contracts with customers |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Union Electric Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
1,094
|
1,315
|
1,945
|
2,208
|
| Operating Segments | Electric | Union Electric Company | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
426
|
405
|
825
|
781
|
| Operating Segments | Electric | Union Electric Company | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
381
|
344
|
683
|
617
|
| Operating Segments | Electric | Union Electric Company | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
94
|
84
|
166
|
150
|
| Operating Segments | Electric | Union Electric Company | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
193
|
482
|
271
|
660
|
| Operating Segments | Electric | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
629
|
573
|
1,272
|
1,145
|
| Operating Segments | Electric | Ameren Illinois Electric Distribution | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
350
|
321
|
699
|
663
|
| Operating Segments | Electric | Ameren Illinois Electric Distribution | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
198
|
181
|
393
|
361
|
| Operating Segments | Electric | Ameren Illinois Electric Distribution | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
52
|
48
|
107
|
98
|
| Operating Segments | Electric | Ameren Illinois Electric Distribution | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
29
|
23
|
73
|
23
|
| Operating Segments | Electric | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Illinois Natural Gas | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Illinois Natural Gas | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Illinois Natural Gas | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Illinois Natural Gas | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
229
|
208
|
456
|
418
|
| Operating Segments | Electric | Ameren Transmission | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Transmission | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Transmission | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Electric | Ameren Transmission | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
229
|
208
|
456
|
418
|
| Operating Segments | Natural gas | Union Electric Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
30
|
25
|
109
|
89
|
| Operating Segments | Natural gas | Union Electric Company | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
16
|
13
|
64
|
56
|
| Operating Segments | Natural gas | Union Electric Company | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
7
|
5
|
27
|
24
|
| Operating Segments | Natural gas | Union Electric Company | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
1
|
1
|
3
|
3
|
| Operating Segments | Natural gas | Union Electric Company | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
6
|
6
|
15
|
6
|
| Operating Segments | Natural gas | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Illinois Electric Distribution | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Illinois Electric Distribution | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Illinois Electric Distribution | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Illinois Electric Distribution | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
176
|
158
|
612
|
569
|
| Operating Segments | Natural gas | Ameren Illinois Natural Gas | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
113
|
107
|
425
|
416
|
| Operating Segments | Natural gas | Ameren Illinois Natural Gas | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
29
|
28
|
115
|
105
|
| Operating Segments | Natural gas | Ameren Illinois Natural Gas | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
2
|
3
|
8
|
7
|
| Operating Segments | Natural gas | Ameren Illinois Natural Gas | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
32
|
20
|
64
|
41
|
| Operating Segments | Natural gas | Ameren Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Transmission | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Transmission | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Transmission | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Natural gas | Ameren Transmission | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Ameren Illinois Company | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
629
|
573
|
1,272
|
1,145
|
| Revenues |
629
|
573
|
1,272
|
1,145
|
| Operating Segments | Ameren Illinois Company | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
176
|
158
|
612
|
569
|
| Revenues |
176
|
158
|
612
|
569
|
| Operating Segments | Ameren Illinois Company | Ameren Illinois Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
123
|
112
|
243
|
229
|
| Revenues |
168
|
152
|
332
|
306
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
629
|
573
|
1,272
|
1,145
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Electric Distribution | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
350
|
321
|
699
|
663
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Electric Distribution | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
198
|
181
|
393
|
361
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Electric Distribution | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
52
|
48
|
107
|
98
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Electric Distribution | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
29
|
23
|
73
|
23
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
168
|
152
|
332
|
306
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Transmission | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Transmission | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Transmission | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Operating Segments | Ameren Illinois Company | Electric | Ameren Illinois Transmission | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
168
|
152
|
332
|
306
|
| Operating Segments | Ameren Illinois Company | Natural gas | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
176
|
158
|
612
|
569
|
| Operating Segments | Ameren Illinois Company | Natural gas | Ameren Illinois Natural Gas | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
113
|
107
|
425
|
416
|
| Operating Segments | Ameren Illinois Company | Natural gas | Ameren Illinois Natural Gas | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
29
|
28
|
115
|
105
|
| Operating Segments | Ameren Illinois Company | Natural gas | Ameren Illinois Natural Gas | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
2
|
3
|
8
|
7
|
| Operating Segments | Ameren Illinois Company | Natural gas | Ameren Illinois Natural Gas | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
32
|
20
|
64
|
41
|
| Intersegment Eliminations |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(66)
|
(58)
|
(126)
|
(111)
|
| Revenues |
(66)
|
(58)
|
(126)
|
(111)
|
| Other revenues not from contracts with customers |
(2)
|
(4)
|
(2)
|
(4)
|
| Intersegment Eliminations | Union Electric Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(13)
|
(8)
|
(23)
|
(15)
|
| Intersegment Eliminations | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
(3)
|
0
|
(5)
|
| Intersegment Eliminations | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Ameren Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(53)
|
(47)
|
(103)
|
(91)
|
| Intersegment Eliminations | Electric |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(65)
|
(58)
|
(125)
|
(111)
|
| Intersegment Eliminations | Electric | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Electric | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Electric | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Electric | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(65)
|
(58)
|
(125)
|
(111)
|
| Intersegment Eliminations | Natural gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(1)
|
0
|
(1)
|
0
|
| Intersegment Eliminations | Natural gas | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Natural gas | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Natural gas | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Natural gas | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(1)
|
0
|
(1)
|
0
|
| Intersegment Eliminations | Ameren Illinois Company |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(45)
|
(40)
|
(89)
|
(77)
|
| Revenues |
(45)
|
(40)
|
(89)
|
(77)
|
| Intersegment Eliminations | Ameren Illinois Company | Residential |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Ameren Illinois Company | Commercial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Ameren Illinois Company | Industrial |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Operating Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Ameren Illinois Company | Other |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
(45)
|
(40)
|
(89)
|
(77)
|
| Intersegment Eliminations | Ameren Illinois Company | Ameren Illinois Electric Distribution |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Ameren Illinois Company | Ameren Illinois Natural Gas |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
0
|
0
|
0
|
0
|
| Intersegment Eliminations | Ameren Illinois Company | Ameren Illinois Transmission |
|
|
|
|
| Disaggregation of Revenue [Line Items] |
|
|
|
|
| Revenues |
$ (45)
|
$ (40)
|
$ (89)
|
$ (77)
|