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v3.19.3.a.u2

Financings And Capitalization (Major Long-Term Debt Transactions) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Debt Instrument [Line Items] |
Principal Balance | $ 2,096
Debt retirement, principal | 945
Consumers Energy Company |
Debt Instrument [Line Items] |
Debt retirement, principal | 300
First Mortgage Bonds | 3.750% First Mortgage Bonds Due 2050 | Consumers Energy Company |
Debt Instrument [Line Items] |
Principal Balance | $ 300
Interest rate | 3.75%
First Mortgage Bonds | 3.100% First Mortgage Bonds Due 2050 | Consumers Energy Company |
Debt Instrument [Line Items] |
Principal Balance | $ 550
Interest rate | 3.10%
First Mortgage Bonds | Variable Rate First Mortgage Bonds | Consumers Energy Company |
Debt Instrument [Line Items] |
Principal Balance | $ 76
First Mortgage Bonds | 5.650% First Mortgage Bonds Due 2020 | Consumers Energy Company |
Debt Instrument [Line Items] |
Debt retirement, principal | $ 300
Interest rate | 5.65%
Tax Exempt Revenue Bonds | Variable Tax Exempt Revenue Bonds Due 2049 | Consumers Energy Company |
Debt Instrument [Line Items] |
Principal Balance | $ 75
Interest rate | 1.80%
First Mortgage Bonds and Tax Exempt Revenue Bonds | Consumers Energy Company |
Debt Instrument [Line Items] |
Principal Balance | $ 1,001
CMS Energy |
Debt Instrument [Line Items] |
Debt retirement, principal | 645
CMS Energy | Term Loan Facility Due 2019 |
Debt Instrument [Line Items] |
Debt retirement, principal | 300
CMS Energy | Term Loan Facility Due April 2019 |
Debt Instrument [Line Items] |
Debt retirement, principal | 180
CMS Energy | Term loans and revolving credit agreements | Term Loan Facility Due 2019 |
Debt Instrument [Line Items] |
Principal Balance | 300
CMS Energy | Term loans and revolving credit agreements | Term Loan Facility Due 2020 |
Debt Instrument [Line Items] |
Principal Balance | 165
CMS Energy | Junior subordinated notes¹ |
Debt Instrument [Line Items] |
Principal Balance | 1,095
CMS Energy | Junior subordinated notes¹ | 5.875% Junior Subordinated Notes Due 2079 |
Debt Instrument [Line Items] |
Principal Balance | $ 630
Interest rate | 5.875%
Term Loan Facility Due June 2020 Tranche One | CMS Energy | Term Loan Facility Due 2020 |
Debt Instrument [Line Items] |
Debt retirement, principal | $ 165

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