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v3.19.3.a.u2

Reportable Segments (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue | $ 1,795 | $ 1,546 | $ 1,445 | $ 2,059 | $ 1,829 | $ 1,599 | $ 1,492 | $ 1,953 | $ 6,845 | $ 6,873 | $ 6,583
Depreciation and amortization |  |  |  |  |  |  |  |  | 992 | 933 | 881
Income from equity method investees |  |  |  |  |  |  |  |  | 10 | 9 | 15
Interest charges |  |  |  |  |  |  |  |  | 519 | 458 | 438
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 147 | 115 | 424
Net income (loss) available to common stockholders | 167 | 207 | 93 | 213 | 108 | 169 | 139 | 241 | 680 | 657 | 460
Plant, property, and equipment, gross | 25,390 |  |  |  | 24,400 |  |  |  | 25,390 | 24,400 | 22,506
Investments in equity method investees | 71 |  |  |  | 69 |  |  |  | 71 | 69 | 64
Total assets | 26,837 |  |  |  | 24,529 |  |  |  | 26,837 | 24,529 | 23,050
Capital expenditures |  |  |  |  |  |  |  |  | 2,147 | 2,081 | 1,722
Consumers Energy Company |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue | 1,670 | 1,429 | 1,334 | 1,943 | 1,712 | 1,502 | 1,395 | 1,855 | 6,376 | 6,464 | 6,222
Depreciation and amortization |  |  |  |  |  |  |  |  | 975 | 921 | 872
Interest charges |  |  |  |  |  |  |  |  | 297 | 289 | 276
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 185 | 142 | 339
Net income (loss) available to common stockholder | 205 | $ 213 | $ 97 | $ 226 | 130 | $ 180 | $ 151 | $ 242 | 741 | 703 | 630
Plant, property, and equipment, gross | 24,963 |  |  |  | 23,963 |  |  |  | 24,963 | 23,963 | 22,318
Total assets | 23,699 |  |  |  | 22,025 |  |  |  | 23,699 | 22,025 | 21,099
Capital expenditures |  |  |  |  |  |  |  |  | 2,134 | 1,825 | 1,683
Other reconciling items |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization |  |  |  |  |  |  |  |  | 1 | 0 | 0
Interest charges |  |  |  |  |  |  |  |  | 157 | 136 | 144
Income tax expense (benefit) |  |  |  |  |  |  |  |  | (56) | (41) | (11)
Net income (loss) available to common stockholders |  |  |  |  |  |  |  |  | (144) | (119) | (169)
Plant, property, and equipment, gross | 20 |  |  |  | 17 |  |  |  | 20 | 17 | 17
Total assets | 48 |  |  |  | 98 |  |  |  | 48 | 98 | 210
Capital expenditures |  |  |  |  |  |  |  |  | 1 | 2 | 1
Other reconciling items | Consumers Energy Company |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization |  |  |  |  |  |  |  |  | 1 | 0 | 0
Interest charges |  |  |  |  |  |  |  |  | 1 | 1 | 1
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 0 | 0 | (2)
Net income (loss) available to common stockholder |  |  |  |  |  |  |  |  | (1) | (1) | 2
Plant, property, and equipment, gross | 20 |  |  |  | 17 |  |  |  | 20 | 17 | 17
Total assets | 20 |  |  |  | 29 |  |  |  | 20 | 29 | 53
Capital expenditures |  |  |  |  |  |  |  |  | 1 | 2 | 1
Electric Utility | Operating Segments |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 4,439 | 4,561 | 4,448
Depreciation and amortization |  |  |  |  |  |  |  |  | 713 | 682 | 654
Interest charges |  |  |  |  |  |  |  |  | 213 | 209 | 201
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 134 | 109 | 245
Net income (loss) available to common stockholders |  |  |  |  |  |  |  |  | 509 | 535 | 455
Plant, property, and equipment, gross | 16,158 |  |  |  | 16,027 |  |  |  | 16,158 | 16,027 | 15,221
Total assets | 14,911 |  |  |  | 14,079 |  |  |  | 14,911 | 14,079 | 13,906
Capital expenditures |  |  |  |  |  |  |  |  | 1,162 | 865 | 882
Electric Utility | Operating Segments | Consumers Energy Company |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 4,439 | 4,561 | 4,448
Depreciation and amortization |  |  |  |  |  |  |  |  | 713 | 682 | 654
Interest charges |  |  |  |  |  |  |  |  | 213 | 209 | 201
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 134 | 109 | 245
Net income (loss) available to common stockholder |  |  |  |  |  |  |  |  | 509 | 535 | 455
Plant, property, and equipment, gross | 16,158 |  |  |  | 16,027 |  |  |  | 16,158 | 16,027 | 15,221
Total assets | 14,973 |  |  |  | 14,143 |  |  |  | 14,973 | 14,143 | 13,907
Capital expenditures |  |  |  |  |  |  |  |  | 1,162 | 865 | 882
Gas Utility | Operating Segments |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 1,937 | 1,903 | 1,774
Depreciation and amortization |  |  |  |  |  |  |  |  | 261 | 239 | 218
Interest charges |  |  |  |  |  |  |  |  | 83 | 79 | 74
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 51 | 33 | 96
Net income (loss) available to common stockholders |  |  |  |  |  |  |  |  | 233 | 169 | 173
Plant, property, and equipment, gross | 8,785 |  |  |  | 7,919 |  |  |  | 8,785 | 7,919 | 7,080
Total assets | 8,659 |  |  |  | 7,806 |  |  |  | 8,659 | 7,806 | 7,139
Capital expenditures |  |  |  |  |  |  |  |  | 971 | 958 | 800
Gas Utility | Operating Segments | Consumers Energy Company |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 1,937 | 1,903 | 1,774
Depreciation and amortization |  |  |  |  |  |  |  |  | 261 | 239 | 218
Interest charges |  |  |  |  |  |  |  |  | 83 | 79 | 74
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 51 | 33 | 96
Net income (loss) available to common stockholder |  |  |  |  |  |  |  |  | 233 | 169 | 173
Plant, property, and equipment, gross | 8,785 |  |  |  | 7,919 |  |  |  | 8,785 | 7,919 | 7,080
Total assets | 8,706 |  |  |  | 7,853 |  |  |  | 8,706 | 7,853 | 7,139
Capital expenditures |  |  |  |  |  |  |  |  | 971 | 958 | 800
Enterprises | Operating Segments |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 248 | 252 | 229
Depreciation and amortization |  |  |  |  |  |  |  |  | 14 | 8 | 6
Income from equity method investees |  |  |  |  |  |  |  |  | 10 | 9 | 15
Interest charges |  |  |  |  |  |  |  |  | 7 | 2 | 0
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 2 | 2 | 72
Net income (loss) available to common stockholders |  |  |  |  |  |  |  |  | 33 | 34 | (27)
Plant, property, and equipment, gross | 405 |  |  |  | 412 |  |  |  | 405 | 412 | 167
Investments in equity method investees | 71 |  |  |  | 69 |  |  |  | 71 | 69 | 64
Total assets | 527 |  |  |  | 540 |  |  |  | 527 | 540 | 342
Capital expenditures |  |  |  |  |  |  |  |  | 5 | 246 | 33
Enterprises | Operating Segments | Consumers Energy Company |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 0 | 0 |
EnerBank | Operating Segments |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | 221 | 157 | 132
Depreciation and amortization |  |  |  |  |  |  |  |  | 3 | 4 | 3
Interest charges |  |  |  |  |  |  |  |  | 59 | 32 | 19
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 16 | 12 | 22
Net income (loss) available to common stockholders |  |  |  |  |  |  |  |  | 49 | 38 | 28
Plant, property, and equipment, gross | 22 |  |  |  | 25 |  |  |  | 22 | 25 | 21
Total assets | $ 2,692 |  |  |  | $ 2,006 |  |  |  | 2,692 | 2,006 | 1,453
Capital expenditures |  |  |  |  |  |  |  |  | 8 | 10 | $ 6
EnerBank | Operating Segments | Consumers Energy Company |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  | $ 0 | $ 0 |

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