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Quarterly Financial And Common Stock Information (Unaudited) | 12 Months Ended
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Dec. 31, 2018
Quarterly Financial and Common Stock Information [Line Items] |
Quarterly Financial and Common Stock Information (Unaudited) | Quarterly Financial and Common Stock Information (Unaudited)
In Millions, Except Per Share Amounts |
| 2018
Quarters Ended | March 31 |  | June 30 |  | Sept 30 |  | Dec 31 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,953 |  |  | $ | 1,492 |  |  | $ | 1,599 |  |  | $ | 1,829 |
Operating income |  | 363 |  |  | 255 |  |  | 294 |  |  | 250 |
Net income |  | 241 |  |  | 140 |  |  | 169 |  |  | 109 |
Income attributable to noncontrolling interests |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income available to common stockholders |  | 241 |  |  | 139 |  |  | 169 |  |  | 108 |
Basic earnings per average common share 1 |  | 0.86 |  |  | 0.49 |  |  | 0.60 |  |  | 0.38 |
Diluted earnings per average common share 1 |  | 0.86 |  |  | 0.49 |  |  | 0.59 |  |  | 0.38 |
Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,855 |  |  | $ | 1,395 |  |  | $ | 1,502 |  |  | $ | 1,712 |
Operating income |  | 334 |  |  | 229 |  |  | 271 |  |  | 231 |
Net income |  | 242 |  |  | 152 |  |  | 180 |  |  | 131 |
Preferred stock dividends |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income available to common stockholder |  | 242 |  |  | 151 |  |  | 180 |  |  | 130 |
In Millions, Except Per Share Amounts |
| 2017
Quarters Ended | March 31 |  | June 30 |  | Sept 30 |  | Dec 31 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,829 |  |  | $ | 1,449 |  |  | $ | 1,527 |  |  | $ | 1,778 |
Operating income |  | 388 |  |  | 241 |  |  | 330 |  |  | 379 |
Net income (loss) |  | 199 |  |  | 93 |  |  | 172 |  |  | (2 | )
Income attributable to noncontrolling interests |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income (loss) available to common stockholders |  | 199 |  |  | 92 |  |  | 172 |  |  | (3 | )
Basic earnings (loss) per average common share 1 |  | 0.71 |  |  | 0.33 |  |  | 0.61 |  |  | (0.01 | )
Diluted earnings (loss) per average common share 1 |  | 0.71 |  |  | 0.33 |  |  | 0.61 |  |  | (0.01 | )
Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,737 |  |  | $ | 1,362 |  |  | $ | 1,437 |  |  | $ | 1,686 |
Operating income |  | 359 |  |  | 222 |  |  | 308 |  |  | 363 |
Net income |  | 211 |  |  | 104 |  |  | 181 |  |  | 136 |
Preferred stock dividends |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income available to common stockholder |  | 211 |  |  | 103 |  |  | 181 |  |  | 135 |
1 | The sum of the quarters may not equal annual EPS due to changes in the number of shares outstanding.
Consumers Energy Company |
Quarterly Financial and Common Stock Information [Line Items] |
Quarterly Financial and Common Stock Information (Unaudited) | Quarterly Financial and Common Stock Information (Unaudited)
In Millions, Except Per Share Amounts |
| 2018
Quarters Ended | March 31 |  | June 30 |  | Sept 30 |  | Dec 31 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,953 |  |  | $ | 1,492 |  |  | $ | 1,599 |  |  | $ | 1,829 |
Operating income |  | 363 |  |  | 255 |  |  | 294 |  |  | 250 |
Net income |  | 241 |  |  | 140 |  |  | 169 |  |  | 109 |
Income attributable to noncontrolling interests |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income available to common stockholders |  | 241 |  |  | 139 |  |  | 169 |  |  | 108 |
Basic earnings per average common share 1 |  | 0.86 |  |  | 0.49 |  |  | 0.60 |  |  | 0.38 |
Diluted earnings per average common share 1 |  | 0.86 |  |  | 0.49 |  |  | 0.59 |  |  | 0.38 |
Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,855 |  |  | $ | 1,395 |  |  | $ | 1,502 |  |  | $ | 1,712 |
Operating income |  | 334 |  |  | 229 |  |  | 271 |  |  | 231 |
Net income |  | 242 |  |  | 152 |  |  | 180 |  |  | 131 |
Preferred stock dividends |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income available to common stockholder |  | 242 |  |  | 151 |  |  | 180 |  |  | 130 |
In Millions, Except Per Share Amounts |
| 2017
Quarters Ended | March 31 |  | June 30 |  | Sept 30 |  | Dec 31 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,829 |  |  | $ | 1,449 |  |  | $ | 1,527 |  |  | $ | 1,778 |
Operating income |  | 388 |  |  | 241 |  |  | 330 |  |  | 379 |
Net income (loss) |  | 199 |  |  | 93 |  |  | 172 |  |  | (2 | )
Income attributable to noncontrolling interests |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income (loss) available to common stockholders |  | 199 |  |  | 92 |  |  | 172 |  |  | (3 | )
Basic earnings (loss) per average common share 1 |  | 0.71 |  |  | 0.33 |  |  | 0.61 |  |  | (0.01 | )
Diluted earnings (loss) per average common share 1 |  | 0.71 |  |  | 0.33 |  |  | 0.61 |  |  | (0.01 | )
Consumers |  |  |  |  |  |  |  |
Operating revenue |  | $ | 1,737 |  |  | $ | 1,362 |  |  | $ | 1,437 |  |  | $ | 1,686 |
Operating income |  | 359 |  |  | 222 |  |  | 308 |  |  | 363 |
Net income |  | 211 |  |  | 104 |  |  | 181 |  |  | 136 |
Preferred stock dividends |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net income available to common stockholder |  | 211 |  |  | 103 |  |  | 181 |  |  | 135 |
1 | The sum of the quarters may not equal annual EPS due to changes in the number of shares outstanding.

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