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v3.25.0.1

Financings and Capitalization (Narrative) (Details) $ / shares in Units, $ in Millions |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 11, 2025 USD ($) | Dec. 31, 2024 USD ($) $ / shares shares | Jan. 31, 2024 USD ($) $ / shares | Dec. 31, 2024 USD ($) $ / shares shares | Dec. 31, 2023 USD ($) $ / shares shares | Dec. 31, 2022 USD ($)
Financing And Capitalization [Line Items] |  |  |  |  |  |
Principal (In Millions) |  | $ 1,790 |  | $ 1,790 |  |
Payment for purchase of first mortgage bonds |  |  |  | 952 | $ 2,132 | $ 106
Interest on long-term debt |  |  |  | 700 | 616 | 509
Notes payable |  | $ 65 |  | $ 65 | $ 93 |
Supplier Finance Program, Obligation, Statement of Financial Position [Extensible Enumeration] |  | Accounts payable |  | Accounts payable |  |
Limitation on payment of stock dividends |  | $ 8,000 |  | $ 8,000 |  |
Dividends paid |  |  |  | $ 795 |  |
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 |
Issuance of common stock |  |  |  | $ 286 | 192 | 69
Settlement Of Forward Contracts |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Settlement of forward contracts through issuance of stock (in dollars per share) | $ / shares |  |  | $ 70.31 |  |  |
Issuance of common stock |  |  | $ 266 |  |  |
CMS Energy |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Principal (In Millions) |  | $ 490 |  | 490 |  |
Payment for purchase of first mortgage bonds |  |  |  | 250 | 0 | 0
Interest on long-term debt |  |  |  | 205 | 201 | 181
Issuance of common stock |  |  |  | $ 286 | $ 192 | 69
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 |
Depositary share conversion ratio |  | 0.001 |  | 0.001 |  |
Trading symbol |  |  |  | CMS PRC |  |
Consumers Energy Company Cumulative Preferred Stock, $100 par value: $4.50 Series |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Trading symbol |  |  |  | CMS-PB |  |
Consumers Energy Company |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Principal (In Millions) |  | $ 1,300 |  | $ 1,300 |  |
Payment for purchase of first mortgage bonds |  |  |  | 389 | $ 1,654 | 28
Interest on long-term debt |  |  |  | 488 | 415 | 325
Notes payable |  | 65 |  | 65 | $ 93 |
Unrestricted retained earnings |  | $ 2,300 |  | $ 2,300 |  |
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 | Commercial Paper |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Short-term debt authorized borrowings |  |  |  | $ 500 |  |
Short-term borrowings outstanding |  | $ 65 |  | $ 65 |  |
Weighted average interest rate |  | 4.675% |  | 4.675% |  |
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 |  |
Related Party | Consumers Energy Company |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Principal (In Millions) |  | $ 835 |  | $ 835 | $ 431 |
Related Party | Consumers Energy Company | Credit Agreement |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Maximum borrowing capacity |  | $ 500 |  | 500 |  |
Basis spread on variable rate |  | (0.10%) |  |  |  |
Notes payable |  | $ 0 |  | 0 |  |
Construction Loans | Construction Financing Agreement | NorthStar Clean Energy, Including Subsidiaries | Subsequent Event |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Maximum borrowing capacity | $ 334 |  |  |  |  |
Borrowings | $ 32 |  |  |  |  |
Interest Rate (%) | 6.60% |  |  |  |  |
First mortgage bonds |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  | 110 | 131 | $ 0
First mortgage bonds | Repurchased Debt |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Interest on long-term debt |  |  |  | 19 | 5 |
First mortgage bonds | Related Party | Consumers Energy Company |  |  |  |  |  |
Financing And Capitalization [Line Items] |  |  |  |  |  |
Principal (In Millions) |  | $ 404 |  | 404 | 431 |
Payment for purchase of first mortgage bonds |  |  |  | $ 289 | $ 293 |

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