v3.25.4
Financings and Capitalization (Narrative) (Details)
$ / shares in Units, $ in Millions
 1 Months Ended 12 Months Ended
Dec. 31, 2024
USD ($)
$ / shares
shares
Dec. 31, 2025
USD ($)
$ / shares
shares
Dec. 31, 2025
USD ($)
$ / shares
shares
Dec. 31, 2023
USD ($)
Financing And Capitalization [Line Items]        
Notes payable $ 65 $ 0 $ 0  
Limitation on payment of stock dividends   $ 8,900 8,900  
Dividends paid     $ 898  
Common stock authorized (in shares) | shares 350,000,000.0 350,000,000.0 350,000,000.0  
Common Stock, par value (in dollars per share) | $ / shares   $ 0.01 $ 0.01  
Preferred stock authorized (in shares) | shares   10,000,000 10,000,000  
Preferred stock, par value (in dollars per share) | $ / shares   $ 0.01 $ 0.01  
Stock offering program maximum value       $ 1,000
Shares contracted under forward sale agreements (in shares) | shares 400,000 6,700,000 6,700,000  
Initial forward price (in dollars per share) | $ / shares $ 69.43   $ 71.08  
Series C Preferred Stock Depositary Shares        
Financing And Capitalization [Line Items]        
Preferred stock authorized (in shares) | shares 9,200,000 9,200,000 9,200,000  
Preferred stock, par value (in dollars per share) | $ / shares $ 25 $ 25 $ 25  
Trading Symbol     CMS PRC  
Depositary share conversion ratio   0.001 0.001  
Consumers Energy Company Cumulative Preferred Stock, $100 par value: $4.50 Series        
Financing And Capitalization [Line Items]        
Trading Symbol     CMS-PB  
Settlement Of Forward Contracts        
Financing And Capitalization [Line Items]        
Shares subject to forward equity sale agreement (in shares) | shares     7,000,000  
Settlement of forward contracts through issuance of stock (in dollars per share) | $ / shares   $ 71.16 $ 71.16  
Issuance of common stock     $ 497  
Aggregate sales price   $ 8 8  
Consumers Energy Company        
Financing And Capitalization [Line Items]        
Unrestricted retained earnings   $ 2,500 $ 2,500  
Common stock authorized (in shares) | shares 125,000,000.0 125,000,000.0 125,000,000.0  
Preferred stock authorized (in shares) | shares 7,500,000 7,500,000 7,500,000  
Preferred stock, par value (in dollars per share) | $ / shares $ 4.50 $ 4.50 $ 4.50  
Consumers Energy Company | Related Party        
Financing And Capitalization [Line Items]        
Notes payable $ 0 $ 340 $ 340  
Consumers Energy Company | Credit Agreement | Related Party        
Financing And Capitalization [Line Items]        
Maximum borrowing capacity   $ 500 500  
Basis spread on variable rate   (0.10%)    
Notes payable   $ 340 $ 340  
Interest rate at period end   3.859% 3.859%  
NorthStar Clean Energy        
Financing And Capitalization [Line Items]        
Supplier financing program, payment period   135 days 135 days  
Supplier financing program, termination period   30 days 30 days  
NorthStar Clean Energy | NorthStar Clean Energy's Supplier Financing Program        
Financing And Capitalization [Line Items]        
Supplier Finance Program, Obligation, Statement of Financial Position [Extensible Enumeration]   Accounts payable Accounts payable  
Commercial Paper | Consumers Energy Company        
Financing And Capitalization [Line Items]        
Short-term debt authorized borrowings     $ 500  
Short-term borrowings outstanding   $ 0 $ 0