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v3.19.1

Reportable Segments (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | $ 2,059 | $ 1,953 |
Net income | 213 | 241 |
Plant, property, and equipment, gross | 24,729 |  | $ 24,400
Total Assets | 24,793 |  | 24,529
Consumers Energy Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 1,943 | 1,855 |
Net income | 226 | 242 |
Plant, property, and equipment, gross | 24,300 |  | 23,963
Total Assets | 22,052 |  | 22,025
Operating Segments | Electric Utility |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 1,103 | 1,078 |
Net income | 105 | 139 |
Plant, property, and equipment, gross | 16,196 |  | 16,027
Total Assets | 14,237 |  | 14,079
Operating Segments | Electric Utility | Consumers Energy Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 1,103 | 1,078 |
Net income | 105 | 139 |
Plant, property, and equipment, gross | 16,196 |  | 16,027
Total Assets | 14,300 |  | 14,143
Operating Segments | Gas Utility |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 840 | 777 |
Net income | 121 | 103 |
Plant, property, and equipment, gross | 8,087 |  | 7,919
Total Assets | 7,681 |  | 7,806
Operating Segments | Gas Utility | Consumers Energy Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 840 | 777 |
Net income | 121 | 103 |
Plant, property, and equipment, gross | 8,087 |  | 7,919
Total Assets | 7,729 |  | 7,853
Operating Segments | Enterprises |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 67 | 63 |
Net income | 1 | 15 |
Plant, property, and equipment, gross | 404 |  | 412
Total Assets | 524 |  | 540
Operating Segments | Enterprises | Consumers Energy Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 0 | 0 |
Other reconciling items |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 49 | 35 |
Net income | (14) | (16) |
Plant, property, and equipment, gross | 42 |  | 42
Total Assets | 2,351 |  | 2,104
Other reconciling items | Consumers Energy Company |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 0 | $ 0 |
Plant, property, and equipment, gross | 17 |  | 17
Total Assets | $ 23 |  | $ 29

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