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v3.20.4

Financings and Capitalization (Summary of Long-Term Debt Outstanding) (Details) - USD ($) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Oct. 31, 2022 | Dec. 31, 2020 | Dec. 31, 2019
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 15,272,000,000 | $ 13,188,000,000
Current amounts |  | (1,486,000,000) | (1,111,000,000)
Unamortized discounts |  | (33,000,000) | (27,000,000)
Unamortized issuance costs |  | (119,000,000) | (99,000,000)
Long-term debt |  | 13,634,000,000 | 11,951,000,000
Consumers Energy Company |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | 8,197,000,000 | 7,322,000,000
Current amounts |  | (364,000,000) | (202,000,000)
Unamortized discounts |  | (29,000,000) | (23,000,000)
Unamortized issuance costs |  | (62,000,000) | (49,000,000)
Long-term debt |  | 7,742,000,000 | 7,048,000,000
Certificates of deposit | EnerBank Certificates Of Deposit | EnerBank |  |  |
Debt Instrument [Line Items] |  |  |
Certificates of deposit |  | $ 2,805,000,000 | $ 2,389,000,000
Weighted-average interest rate |  | 1.621% | 2.445%
Certificate of deposit face value |  | $ 1,000 |
First Mortgage Bonds | Consumers Energy Company |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 7,897,000,000 | $ 6,961,000,000
First Mortgage Bonds | Consumers Energy Company | 3.770% Percent First Mortgage Bonds Due 2020 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.77% |
Principal amounts outstanding |  | $ 0 | 100,000,000
First Mortgage Bonds | Consumers Energy Company | 2.850% First Mortgage Bonds Due 2022 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 2.85% |
Principal amounts outstanding |  | $ 0 | 375,000,000
First Mortgage Bonds | Consumers Energy Company | 5.300% First Mortgage Bonds Due 2022 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 5.30% |
Principal amounts outstanding |  | $ 0 | 250,000,000
First Mortgage Bonds | Consumers Energy Company | 3.375% First Mortgage Bonds Due 2023 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.375% |
Principal amounts outstanding |  | $ 325,000,000 | 325,000,000
First Mortgage Bonds | Consumers Energy Company | 0.350% First Mortgage Bonds Due 2023 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 0.35% |
Principal amounts outstanding |  | $ 300,000,000 | 0
First Mortgage Bonds | Consumers Energy Company | 3.125% First Mortgage Bonds Due 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.125% |
Principal amounts outstanding |  | $ 250,000,000 | 250,000,000
First Mortgage Bonds | Consumers Energy Company | 3.190% First Mortgage Bonds Due 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.19% |
Principal amounts outstanding |  | $ 52,000,000 | 52,000,000
First Mortgage Bonds | Consumers Energy Company | 3.680% First Mortgage Bonds Due 2027 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.68% |
Principal amounts outstanding |  | $ 100,000,000 | 100,000,000
First Mortgage Bonds | Consumers Energy Company | 3.390 % First Mortgage Bonds Due 2027 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.39% |
Principal amounts outstanding |  | $ 35,000,000 | 35,000,000
First Mortgage Bonds | Consumers Energy Company | 3.800% First Mortgage Bonds Due 2028 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.80% |
Principal amounts outstanding |  | $ 300,000,000 | 300,000,000
First Mortgage Bonds | Consumers Energy Company | 3.180% First Mortgage Bonds Due 2032 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.18% |
Principal amounts outstanding |  | $ 100,000,000 | 100,000,000
First Mortgage Bonds | Consumers Energy Company | 5.800 % First Mortgage Bonds Due 2035 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 5.80% |
Principal amounts outstanding |  | $ 175,000,000 | 175,000,000
First Mortgage Bonds | Consumers Energy Company | 3.520% First Mortgage Bonds Due 2037 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.52% |
Principal amounts outstanding |  | $ 335,000,000 | 335,000,000
First Mortgage Bonds | Consumers Energy Company | 4.010% First Mortgage Bonds Due 2038 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.01% |
Principal amounts outstanding |  | $ 215,000,000 | 215,000,000
First Mortgage Bonds | Consumers Energy Company | 6.170% First Mortgage Bonds Due 2040 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 6.17% |
Principal amounts outstanding |  | $ 50,000,000 | 50,000,000
First Mortgage Bonds | Consumers Energy Company | 4.970% First Mortgage Bonds Due 2040 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.97% |
Principal amounts outstanding |  | $ 50,000,000 | 50,000,000
First Mortgage Bonds | Consumers Energy Company | 4.310% First Mortgage Bonds Due 2042 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.31% |
Principal amounts outstanding |  | $ 263,000,000 | 263,000,000
First Mortgage Bonds | Consumers Energy Company | 3.950% First Mortgage Bonds Due 2043 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.95% |
Principal amounts outstanding |  | $ 425,000,000 | 425,000,000
First Mortgage Bonds | Consumers Energy Company | 4.100% First Mortgage Bonds Due 2045 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.10% |
Principal amounts outstanding |  | $ 250,000,000 | 250,000,000
First Mortgage Bonds | Consumers Energy Company | 3.250% First Mortgage Bonds Due 2046 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.25% |
Principal amounts outstanding |  | $ 450,000,000 | 450,000,000
First Mortgage Bonds | Consumers Energy Company | 3.950% First Mortgage Bonds Due 2047 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.95% |
Principal amounts outstanding |  | $ 350,000,000 | 350,000,000
First Mortgage Bonds | Consumers Energy Company | 4.050% First Mortgage Bonds Due 2048 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.05% |
Principal amounts outstanding |  | $ 550,000,000 | 550,000,000
First Mortgage Bonds | Consumers Energy Company | 4.350% First Mortgage Bonds Due 2049 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.35% |
Principal amounts outstanding |  | $ 550,000,000 | 550,000,000
First Mortgage Bonds | Consumers Energy Company | 3.750% First Mortgage Bonds Due 2050 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.75% |
Principal amounts outstanding |  | $ 300,000,000 | 300,000,000
First Mortgage Bonds | Consumers Energy Company | 3.100% First Mortgage Bonds Due 2050 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.10% |
Principal amounts outstanding |  | $ 550,000,000 | 550,000,000
First Mortgage Bonds | Consumers Energy Company | 3.500% First Mortgage Bonds Due 2051 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.50% |
Principal amounts outstanding |  | $ 575,000,000 | 0
First Mortgage Bonds | Consumers Energy Company | 3.860% First Mortgage Bonds Due 2052 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.86% |
Principal amounts outstanding |  | $ 50,000,000 | 50,000,000
First Mortgage Bonds | Consumers Energy Company | 4.280% First Mortgage Bonds Due 2057 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.28% |
Principal amounts outstanding |  | $ 185,000,000 | 185,000,000
First Mortgage Bonds | Consumers Energy Company | 2.500% First Mortgage Bonds Due 2060 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 2.50% |
Principal amounts outstanding |  | $ 525,000,000 | 0
First Mortgage Bonds | Consumers Energy Company | 4.350% First Mortgage Bonds Due 2064 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.35% |
Principal amounts outstanding |  | $ 250,000,000 | 250,000,000
First Mortgage Bonds | Consumers Energy Company | Variable Rate First Mortgage Bonds Due 2069 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | 76,000,000 | 76,000,000
First Mortgage Bonds | Consumers Energy Company | Variable Rate First Mortgage Bonds Due 2070 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | 134,000,000 | 0
First Mortgage Bonds | Consumers Energy Company | Variable Rate First Mortgage Bonds Due 2070 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 127,000,000 | 0
First Mortgage Bonds | Consumers Energy Company | Variable Rate First Mortgage Bonds |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate at period end |  | 0.00% |
Three-month LIBOR plus a spread |  | 0.30% |
Tax Exempt Revenue Bonds | Consumers Energy Company |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 75,000,000 | 110,000,000
Tax Exempt Revenue Bonds | Consumers Energy Company | Tax Exempt Revenue Bonds Due 2035 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | 0 | 35,000,000
Tax Exempt Revenue Bonds | Consumers Energy Company | 1.800% Tax Exempt Revenue Bonds Due 2049 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 75,000,000 | 75,000,000
Weighted average interest rate |  | 1.80% |
Securitization bonds | Consumers Energy Company | Securitization Bonds |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 225,000,000 | $ 251,000,000
Weighted average interest rate |  | 3.25% | 3.22%
CMS Energy |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 4,185,000,000 | $ 3,385,000,000
Long-term debt |  | 3,926,000,000 | 3,334,000,000
CMS Energy | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 1,975,000,000 | 2,275,000,000
CMS Energy | Senior notes | 5.050% Senior Notes Due 2022 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 5.05% |
Principal amounts outstanding |  | $ 0 | 300,000,000
CMS Energy | Senior notes | 3.875% Senior Notes Due 2024 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.875% |
Principal amounts outstanding |  | $ 250,000,000 | 250,000,000
CMS Energy | Senior notes | 3.600% Senior Notes Due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.60% |
Principal amounts outstanding |  | $ 250,000,000 | 250,000,000
CMS Energy | Senior notes | 3.000% Senior Notes Due 2026 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.00% |
Principal amounts outstanding |  | $ 300,000,000 | 300,000,000
CMS Energy | Senior notes | 2.950% Senior Notes Due 2027 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 2.95% |
Principal amounts outstanding |  | $ 275,000,000 | 275,000,000
CMS Energy | Senior notes | 3.450% Senior Notes Due 2027 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.45% |
Principal amounts outstanding |  | $ 350,000,000 | 350,000,000
CMS Energy | Senior notes | 4.700% Senior Notes Due 2043 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.70% |
Principal amounts outstanding |  | $ 250,000,000 | 250,000,000
CMS Energy | Senior notes | 4.875% Senior Notes Due 2044 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.875% |
Principal amounts outstanding |  | $ 300,000,000 | 300,000,000
CMS Energy | Term loans and revolving credit agreements | Term Loan Facility Due 2021 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 200,000,000 | 0
Interest rate at period end |  | 0.60% |
Three-month LIBOR plus a spread |  | 0.50% |
CMS Energy | Junior subordinated notes |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 2,010,000,000 | 1,110,000,000
CMS Energy | Junior subordinated notes | 4.750% Junior Subordinated Notes Due 2050 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 4.75% |
Principal amounts outstanding |  | $ 500,000,000 | 0
CMS Energy | Junior subordinated notes | 3.750% Junior Subordinated Notes Due 2050 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 3.75% |
Principal amounts outstanding |  | $ 400,000,000 | 0
CMS Energy | Junior subordinated notes | 5.625% Junior Subordinated Notes Due 2078 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 5.625% |
Principal amounts outstanding |  | $ 200,000,000 | 200,000,000
CMS Energy | Junior subordinated notes | 5.875% Junior Subordinated Notes Due 2078 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 5.875% |
Principal amounts outstanding |  | $ 280,000,000 | 280,000,000
CMS Energy | Junior subordinated notes | 5.875% Junior Subordinated Notes Due 2079 |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate |  | 5.875% |
Principal amounts outstanding |  | $ 630,000,000 | 630,000,000
CMS Enterprises Including Subsidiaries | Term loans and revolving credit agreements | Term Loan Facility Due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Principal amounts outstanding |  | $ 85,000,000 | $ 92,000,000
Interest rate at period end |  | 1.754% | 3.445%
Three-month LIBOR plus a spread |  | 1.50% |
Fixed interest rate |  | 4.702% |
Forecast | CMS Enterprises Including Subsidiaries | Term loans and revolving credit agreements | Term Loan Facility Due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Three-month LIBOR plus a spread | 1.75% |  |
Fixed interest rate | 4.952% |  |

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