v3.25.4
Reportable Segments (Schedule of Financial Information by Reportable Segments, Consumers) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Segment Reporting Information [Line Items]      
Operating Revenue $ 8,539 $ 7,515 $ 7,462
Power supply cost 2,457 2,028 2,011
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 246 176 147
Net Income 1,071 1,003 887
Other segment items 59 46 70
Net Income (Loss) Available to Common Stockholders 1,061 993 877
Total assets 39,941 35,920  
Capital expenditures 3,970 3,301  
Consumers Energy Company      
Segment Reporting Information [Line Items]      
Operating Revenue 8,132 7,200 7,166
Power supply cost 2,193 1,867 1,841
Cost of gas sold 803 637 897
Maintenance and other operating expenses 1,614 1,520 1,586
Depreciation and amortization 1,254 1,191 1,137
General taxes 499 470 437
Total operating expenses 6,363 5,685 5,898
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 288 200 161
Net Income 1,129 1,009 867
Other segment items (2) (2) (2)
Net Income (Loss) Available to Common Stockholders 1,127 1,007 865
Property, plant, and equipment, gross 36,120 33,434  
Total assets 37,091 34,088  
Capital expenditures 3,472 3,012  
Operating Segments      
Segment Reporting Information [Line Items]      
Operating Revenue 8,539 7,515 7,462
Power supply cost 2,457 2,028 2,011
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 284 196 169
Other segment items 69 56 78
Net Income (Loss) Available to Common Stockholders 1,199 1,072 932
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
Cost of gas sold 803 637 897
Maintenance and other operating expenses 1,614 1,520 1,586
Depreciation and amortization 1,253 1,190 1,135
General taxes 498 469 436
Total operating expenses 6,361 5,683 5,895
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 288 201 165
Net Income 1,130 1,011 867
Other segment items (2) (2) (2)
Net Income (Loss) Available to Common Stockholders 1,128 1,009 865
Property, plant, and equipment, gross 36,089 33,405  
Total assets 37,043 34,056  
Capital expenditures 3,472 3,012  
Operating Segments | Electric Utility      
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 150 102 67
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 719 681 550
Total assets 22,760 20,710  
Capital expenditures 2,408 1,871  
Operating Segments | Electric Utility | 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
Cost of gas sold 0 0 0
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 150 102 67
Net Income 720 682 551
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 719 681 550
Property, plant, and equipment, gross 21,871 20,137  
Total assets 22,814 20,767  
Capital expenditures 2,408 1,871  
Operating Segments | Gas Utility      
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 138 99 98
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 409 328 315
Total assets 14,188 13,247  
Capital expenditures 1,064 1,141  
Operating Segments | Gas Utility | Consumers Energy Company      
Segment Reporting Information [Line Items]      
Operating Revenue 2,493 2,138 2,420
Power supply cost 0 0 0
Cost of gas sold 803 637 897
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 138 99 98
Net Income 410 329 316
Other segment items (1) (1) (1)
Net Income (Loss) Available to Common Stockholders 409 328 315
Property, plant, and equipment, gross 14,218 13,268  
Total assets 14,229 13,289  
Capital expenditures 1,064 1,141  
Other Reconciling Items      
Segment Reporting Information [Line Items]      
Operating Revenue 0 0 0
Power supply cost 0 0 0
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 (38) (20) (22)
Other segment items (10) (10) (8)
Net Income (Loss) Available to Common Stockholders (138) (79) (55)
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
Cost of gas sold 0 0 0
Maintenance and other operating expenses 0 0 0
Depreciation and amortization 1 1 2
General taxes 1 1 1
Total operating expenses 2 2 3
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 0 (1) (4)
Net Income (1) (2) 0
Other segment items 0 0 0
Net Income (Loss) Available to Common Stockholders (1) (2) $ 0
Property, plant, and equipment, gross 31 29  
Total assets 48 32  
Capital expenditures $ 0 $ 0