v3.25.4
Reportable Segments (Schedule of Financial Information by Reportable Segments, CMS Energy, including Consumers) (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2025
USD ($)
Segment
segment
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Segment Reporting Information [Line Items]      
Number of reportable segments | segment 3    
Operating Revenue $ 8,539 $ 7,515 $ 7,462
Power supply cost 2,457 2,028 2,011
Maintenance and other operating expenses 1,727 1,638 1,687
Depreciation and amortization 1,306 1,240 1,180
General taxes 513 482 447
Total operating expenses 6,812 6,028 6,227
Operating Income 1,727 1,487 1,235
Total other income 310 344 362
Total interest charges 789 708 643
Income (Loss) Before Income Taxes 1,248 1,123 954
Income tax expense (benefit) 246 176 147
Income from continuing operations 1,002 947 807
Other segment items 59 46 70
Net Income (Loss) Available to Common Stockholders 1,061 993 877
Plant, property, and equipment, gross 37,763 34,932  
Investments 61 64  
Total assets 39,941 35,920  
Capital expenditures 3,970 3,301  
Income from equity method investees $ 5 7 7
Consumers Energy Company      
Segment Reporting Information [Line Items]      
Number of reportable segments | Segment 2    
Operating Revenue $ 8,132 7,200 7,166
Power supply cost 2,193 1,867 1,841
Operating Income 1,769 1,515 1,268
Total other income 208 212 208
Total interest charges 560 518 448
Income (Loss) Before Income Taxes 1,417 1,209 1,028
Income tax expense (benefit) 288 200 161
Other segment items (2) (2) (2)
Net Income (Loss) Available to Common Stockholders 1,127 1,007 865
Total assets 37,091 34,088  
Capital expenditures 3,472 3,012  
Cost of gas sold      
Segment Reporting Information [Line Items]      
Cost of gas sold 809 640 902
Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenue 8,539 7,515 7,462
Power supply cost 2,457 2,028 2,011
Maintenance and other operating expenses 1,714 1,621 1,674
Depreciation and amortization 1,305 1,239 1,178
General taxes 512 481 446
Total operating expenses 6,797 6,009 6,211
Operating Income 1,742 1,506 1,251
Total other income 224 226 220
Total interest charges 552 520 448
Income (Loss) Before Income Taxes 1,414 1,212 1,023
Income tax expense (benefit) 284 196 169
Income from continuing operations 1,130 1,016 854
Other segment items 69 56 78
Net Income (Loss) Available to Common Stockholders 1,199 1,072 932
Plant, property, and equipment, gross 37,738 34,911  
Investments 61 64  
Total assets 39,444 35,850  
Capital expenditures 3,970 3,300  
Operating Segments | Consumers Energy Company      
Segment Reporting Information [Line Items]      
Operating Revenue 8,131 7,199 7,165
Power supply cost 2,193 1,867 1,841
Operating Income 1,770 1,516 1,270
Total other income 207 212 208
Total interest charges 559 516 446
Income (Loss) Before Income Taxes 1,418 1,212 1,032
Income tax expense (benefit) 288 201 165
Other segment items (2) (2) (2)
Net Income (Loss) Available to Common Stockholders 1,128 1,009 865
Total assets 37,043 34,056  
Capital expenditures 3,472 3,012  
Operating Segments | Cost of gas sold      
Segment Reporting Information [Line Items]      
Cost of gas sold 809 640 902
Other Reconciling Items      
Segment Reporting Information [Line Items]      
Operating Revenue 0 0 0
Power supply cost 0 0 0
Maintenance and other operating expenses 13 17 13
Depreciation and amortization 1 1 2
General taxes 1 1 1
Total operating expenses 15 19 16
Operating Income (15) (19) (16)
Total other income 86 118 142
Total interest charges 237 188 195
Income (Loss) Before Income Taxes (166) (89) (69)
Income tax expense (benefit) (38) (20) (22)
Income from continuing operations (128) (69) (47)
Other segment items (10) (10) (8)
Net Income (Loss) Available to Common Stockholders (138) (79) (55)
Plant, property, and equipment, gross 25 21  
Investments 0 0  
Total assets 497 70  
Capital expenditures 0 1  
Other Reconciling Items | Consumers Energy Company      
Segment Reporting Information [Line Items]      
Operating Revenue 1 1 1
Power supply cost 0 0 0
Operating Income (1) (1) (2)
Total other income 1 0 0
Total interest charges 1 2 2
Income (Loss) Before Income Taxes (1) (3) (4)
Income tax expense (benefit) 0 (1) (4)
Other segment items 0 0 0
Net Income (Loss) Available to Common Stockholders (1) (2) 0
Total assets 48 32  
Capital expenditures 0 0  
Other Reconciling Items | Cost of gas sold      
Segment Reporting Information [Line Items]      
Cost of gas sold 0 0 0
Electric Utility | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenue 5,638 5,061 4,745
Power supply cost 2,193 1,867 1,841
Maintenance and other operating expenses 1,146 1,066 1,075
Depreciation and amortization 903 865 797
General taxes 297 281 260
Total operating expenses 4,539 4,079 3,973
Operating Income 1,099 982 772
Total other income 124 126 131
Total interest charges 353 324 285
Income (Loss) Before Income Taxes 870 784 618
Income tax expense (benefit) 150 102 67
Income from continuing operations 720 682 551
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 719 681 550
Plant, property, and equipment, gross 21,871 20,137  
Investments 0 0  
Total assets 22,760 20,710  
Capital expenditures 2,408 1,871  
Electric Utility | Operating Segments | Consumers Energy Company      
Segment Reporting Information [Line Items]      
Operating Revenue 5,638 5,061 4,745
Power supply cost 2,193 1,867 1,841
Operating Income 1,099 982 772
Total other income 124 126 131
Total interest charges 353 324 285
Income (Loss) Before Income Taxes 870 784 618
Income tax expense (benefit) 150 102 67
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 719 681 550
Total assets 22,814 20,767  
Capital expenditures 2,408 1,871  
Electric Utility | Operating Segments | Cost of gas sold      
Segment Reporting Information [Line Items]      
Cost of gas sold 0 0 0
Gas Utility | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenue 2,493 2,138 2,420
Power supply cost 0 0 0
Maintenance and other operating expenses 468 454 511
Depreciation and amortization 350 325 338
General taxes 201 188 176
Total operating expenses 1,822 1,604 1,922
Operating Income 671 534 498
Total other income 83 86 77
Total interest charges 206 192 161
Income (Loss) Before Income Taxes 548 428 414
Income tax expense (benefit) 138 99 98
Income from continuing operations 410 329 316
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 409 328 315
Plant, property, and equipment, gross 14,218 13,268  
Investments 0 0  
Total assets 14,188 13,247  
Capital expenditures 1,064 1,141  
Gas Utility | Operating Segments | Consumers Energy Company      
Segment Reporting Information [Line Items]      
Operating Revenue 2,493 2,138 2,420
Power supply cost 0 0 0
Operating Income 671 534 498
Total other income 83 86 77
Total interest charges 206 192 161
Income (Loss) Before Income Taxes 548 428 414
Income tax expense (benefit) 138 99 98
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 409 328 315
Total assets 14,229 13,289  
Capital expenditures 1,064 1,141  
Gas Utility | Operating Segments | Cost of gas sold      
Segment Reporting Information [Line Items]      
Cost of gas sold 803 637 897
NorthStar Clean Energy | Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenue 408 316 297
Power supply cost 264 161 170
Maintenance and other operating expenses 100 101 88
Depreciation and amortization 52 49 43
General taxes 14 12 10
Total operating expenses 436 326 316
Operating Income (28) (10) (19)
Total other income 17 14 12
Total interest charges (7) 4 2
Income (Loss) Before Income Taxes (4) 0 (9)
Income tax expense (benefit) (4) (5) 4
Income from continuing operations 0 5 (13)
Other segment items 71 58 80
Net Income (Loss) Available to Common Stockholders 71 63 67
Plant, property, and equipment, gross 1,649 1,506  
Investments 61 64  
Total assets 2,496 1,893  
Capital expenditures 498 288  
NorthStar Clean Energy | Operating Segments | Cost of gas sold      
Segment Reporting Information [Line Items]      
Cost of gas sold $ 6 $ 3 $ 5