Consolidated Statements of Income (Unaudited) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Operating Revenue $ 1,864 $ 2,059
Operating Expenses    
Fuel for electric generation 103 142
Purchased power – related parties 18 18
Maintenance and other operating expenses 315 354
Depreciation and amortization 316 298
General taxes 114 106
Total operating expenses 1,496 1,700
Operating Income 368 359
Other Income (Expense)    
Interest income 1 1
Interest and dividend income – related parties 7 0
Allowance for equity funds used during construction 1 2
Income (loss) from equity method investees 3 (1)
Nonoperating retirement benefits, net 31 23
Other income 0 1
Other expense (4) (3)
Total other income 39 23
Interest Charges    
Interest on long-term debt 116 106
Interest expense – related parties 3 0
Other interest expense 19 16
Allowance for borrowed funds used during construction (1) (1)
Total interest charges 137 121
Income Before Income Taxes 270 261
Income Tax Expense 27 48
Net Income $ 243 $ 213
Basic earnings per average common share (in dollars per share) $ 0.86 $ 0.75
Diluted earnings per average common share (in dollars per share) $ 0.85 $ 0.75
Consumers Energy Company    
Operating Revenue $ 1,744 $ 1,943
Operating Expenses    
Fuel for electric generation 79 106
Purchased and interchange power 347 374
Purchased power – related parties 18 18
Cost of gas sold 270 401
Maintenance and other operating expenses 278 319
Depreciation and amortization 312 294
General taxes 111 103
Total operating expenses 1,415 1,615
Operating Income 329 328
Other Income (Expense)    
Interest income 1 1
Interest and dividend income – related parties 1 1
Allowance for equity funds used during construction 1 2
Nonoperating retirement benefits, net 29 21
Other income 0 1
Other expense (3) (3)
Total other income 29 23
Interest Charges    
Interest on long-term debt 74 69
Interest expense – related parties 3 0
Other interest expense 3 3
Allowance for borrowed funds used during construction (1) (1)
Total interest charges 79 71
Income Before Income Taxes 279 280
Income Tax Expense 44 54
Net Income 235 226
Purchased and interchange power    
Operating Expenses    
Cost of sales 357 378
Cost of gas sold    
Operating Expenses    
Cost of sales $ 273 $ 404