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Financings And Capitalization (Tables) | 12 Months Ended
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Dec. 31, 2019
Debt Instrument [Line Items] |
Summary Of Long-Term Debt Outstanding | Presented in the following table is CMS Energy’s long-term debt at December 31:
In Millions |
| Interest Rate (%) | Maturity | 2019 |  | 2018 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
CMS Energy, parent only |  |  |  |  |  |  |  |
Senior notes | 5.050 |  | 2022 |  |  | $ | 300 |  |  | $ | 300 |
| 3.875 |  | 2024 |  |  | 250 |  |  | 250 |
| 3.600 |  | 2025 |  |  | 250 |  |  | 250 |
| 3.000 |  | 2026 |  |  | 300 |  |  | 300 |
| 2.950 |  | 2027 |  |  | 275 |  |  | 275 |
| 3.450 |  | 2027 |  |  | 350 |  |  | 350 |
| 4.700 |  | 2043 |  |  | 250 |  |  | 250 |
| 4.875 |  | 2044 |  |  | 300 |  |  | 300 |
Total senior notes |  |  |  |  |  | $ | 2,275 |  |  | $ | 2,275 |
Term loans and revolving credit agreements | variable |  | 2019 |  |  | — |  |  | 180 |
| variable |  | 2023 |  |  | — |  |  | 30 |
|  |  |  |  |  | $ | — |  |  | $ | 210 |
Junior subordinated notes¹ | 5.625 |  | 2078 |  |  | 200 |  |  | 200 |
| 5.875 |  | 2078 |  |  | 280 |  |  | 280 |
| 5.875 |  | 2079 |  |  | 630 |  |  | — |
|  |  |  |  |  | $ | 1,110 |  |  | $ | 480 |
Total CMS Energy, parent only |  |  |  |  |  | $ | 3,385 |  |  | $ | 2,965 |
CMS Energy subsidiaries |  |  |  |  |  |  |  |
CMS Enterprises, including subsidiaries |  |  |  |  |  |  |  |
Term loan facility | variable | 2 | 2025 |  |  | $ | 92 |  |  | $ | 98 |
EnerBank |  |  |  |  |  |  |  |
Certificates of deposit | 2.445 | 3 | 2020-2027 |  |  | 2,389 |  |  | 1,758 |
Consumers |  |  |  |  |  | 7,322 |  |  | 6,862 |
Total principal amount outstanding |  |  |  |  |  | $ | 13,188 |  |  | $ | 11,683 |
Current amounts |  |  |  |  |  | (1,111 | ) |  | (974 | )
Unamortized discounts |  |  |  |  |  | (27 | ) |  | (21 | )
Unamortized issuance costs |  |  |  |  |  | (99 | ) |  | (73 | )
Total long-term debt |  |  |  |  |  | $ | 11,951 |  |  | $ | 10,615 |
1 | These unsecured obligations rank subordinate and junior in right of payment to all of CMS Energy’s existing and future senior indebtedness.
2 | A subsidiary of CMS Enterprises issued non‑recourse debt to finance the acquisition of a wind generation project in Northwest Ohio. The debt bears interest at an annual interest rate of LIBOR plus 1.500 percent through October 2022 (3.445 percent at December 31, 2019 and 4.303 percent at December 31, 2018). Beginning in October 2022, the debt will bear interest at an annual interest rate of LIBOR plus 1.750 percent. The same subsidiary of CMS Enterprises entered into interest rate swaps with the lending banks to fix the interest charges associated with the debt, at a rate of 4.702 percent through October 2022 and 4.952 percent beginning in October 2022. Principal and interest payments are made quarterly. For information about the interest rate swaps, see Note 6, Fair Value Measurements.
3 The weighted-average interest rate for EnerBank’s certificates of deposit was 2.445 percent at December 31, 2019 and 2.440 percent at December 31, 2018. EnerBank’s primary deposit product consists of brokered certificates of deposit with varying maturities and having a face value of $1,000.
Major Long-Term Debt Transactions | Presented in the following table is a summary of major long-term debt retirements during the year ended December 31, 2019:
| Principal (In Millions) |  | Interest Rate (%) |  | Retirement Date | Maturity Date
CMS Energy, parent only |  |  |  |  |
Term loan facility |  | $ | 300 |  | variable |  | February | December 2019
Term loan facility |  | 180 |  | variable |  | February | April 2019
Term loan facility |  | 165 |  | variable |  | August-December | June 2020
Total CMS Energy, parent only |  | $ | 645 |  |  |  |
Consumers |  |  |  |  |
First mortgage bonds |  | $ | 300 |  | 5.650 | % | May | April 2020
Total Consumers |  | $ | 300 |  |  |  |
Total CMS Energy |  | $ | 945 |  |  |  |
Presented in the following table is a summary of major long-term debt issuances during the year ended December 31, 2019:
| Principal (In Millions) |  | Interest Rate (%) | Issuance Date | Maturity Date
CMS Energy, parent only |  |  |  |  |
Term loan facility |  | $ | 300 |  | variable | January | December 2019
Junior subordinated notes 1 |  | 630 |  | 5.875 | February | March 2079
Term loan facility |  | 165 |  | variable | June | June 2020
Total CMS Energy, parent only |  | $ | 1,095 |  |  |  |
Consumers |  |  |  |  |
First mortgage bonds |  | $ | 300 |  | 3.750 | May | February 2050
First mortgage bonds |  | 550 |  | 3.100 | September | August 2050
First mortgage bonds |  | 76 |  | variable | September | September 2069
Tax-exempt revenue bonds |  | 75 |  | 1.800 | October | October 2049
Total Consumers |  | $ | 1,001 |  |  |  |
Total CMS Energy |  | $ | 2,096 |  |  |  |
1 These unsecured obligations rank subordinate and junior in right of payment to all of CMS Energy’s existing and future senior indebtedness.
Debt Maturities | At December 31, 2019, the aggregate annual contractual maturities for long-term debt for the next five years were:
In Millions |
| 2020 |  | 2021 |  | 2022 |  | 2023 |  | 2024 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |
Long-term debt |  | $ | 1,111 |  |  | $ | 538 |  |  | $ | 1,354 |  |  | $ | 669 |  |  | $ | 808 |
Consumers |  |  |  |  |  |  |  |  |  |
Long-term debt |  | $ | 202 |  |  | $ | 27 |  |  | $ | 653 |  |  | $ | 354 |  |  | $ | 332 |
Revolving Credit Facilities | The following revolving credit facilities with banks were available at December 31, 2019:
In Millions |
Expiration Date | Amount of Facility |  | Amount Borrowed |  | Letters of Credit Outstanding |  | Amount Available |
CMS Energy, parent only |  |  |  |  |  |  |  |
June 5, 2023 1 |  | $ | 550 |  |  | $ | — |  |  | $ | 6 |  |  | $ | 544 |
CMS Enterprises, including subsidiaries |  |  |  |  |  |  |  |
September 30, 2025 2 |  | $ | 18 |  |  | $ | — |  |  | $ | 8 |  |  | $ | 10 |
Consumers 3 |  |  |  |  |  |  |  |
June 5, 2023 |  | $ | 850 |  |  | $ | — |  |  | $ | 7 |  |  | $ | 843 |
November 19, 2021 |  | 250 |  |  | — |  |  | 10 |  |  | 240 |
April 18, 2022 |  | 30 |  |  | — |  |  | 30 |  |  | — |
1 | During the year ended December 31, 2019, CMS Energy’s average borrowings totaled $5 million with a weighted-average interest rate of 3.859 percent.
2 | Under this facility, $8 million is available solely for the purpose of issuing letters of credit. Obligations under this facility are secured by the collateral accounts with the lending bank. There were no borrowings under this facility during the year ended December 31, 2019.
3 Obligations under these facilities are secured by first mortgage bonds of Consumers. During the year ended December 31, 2019, Consumers’ average borrowings totaled $2 million with a weighted-average interest rate of 3.225 percent.
Schedule of Forward Contracts | Presented in the following table are details of these contracts:
Contract Date | Maturity Date | Number of Shares |  | Initial Forward Price Per Share |
November 16, 2018 | May 16, 2020 | 2,017,783 |  |  | $ | 49.06 |
November 20, 2018 | May 20, 2020 | 777,899 |  |  | 50.91 |
February 21, 2019 | August 21, 2020 | 2,083,340 |  |  | 52.27 |
Consumers Energy Company |
Debt Instrument [Line Items] |
Summary Of Long-Term Debt Outstanding | Presented in the following table is Consumers’ long-term debt at December 31:
In Millions |
| Interest Rate (%) | Maturity | 2019 |  | 2018 |
Consumers |  |  |  |  |  |  |  |
First mortgage bonds | 5.650 |  |  | 2020 |  |  | $ | — |  |  | $ | 300 |
| 3.770 |  |  | 2020 |  |  | 100 |  |  | 100 |
| 2.850 |  |  | 2022 |  |  | 375 |  |  | 375 |
| 5.300 |  |  | 2022 |  |  | 250 |  |  | 250 |
| 3.375 |  |  | 2023 |  |  | 325 |  |  | 325 |
| 3.125 |  |  | 2024 |  |  | 250 |  |  | 250 |
| 3.190 |  |  | 2024 |  |  | 52 |  |  | 52 |
| 3.680 |  |  | 2027 |  |  | 100 |  |  | 100 |
| 3.390 |  |  | 2027 |  |  | 35 |  |  | 35 |
| 3.800 |  |  | 2028 |  |  | 300 |  |  | 300 |
| 3.180 |  |  | 2032 |  |  | 100 |  |  | 100 |
| 5.800 |  |  | 2035 |  |  | 175 |  |  | 175 |
| 3.520 |  |  | 2037 |  |  | 335 |  |  | 335 |
| 4.010 |  |  | 2038 |  |  | 215 |  |  | 215 |
| 6.170 |  |  | 2040 |  |  | 50 |  |  | 50 |
| 4.970 |  |  | 2040 |  |  | 50 |  |  | 50 |
| 4.310 |  |  | 2042 |  |  | 263 |  |  | 263 |
| 3.950 |  |  | 2043 |  |  | 425 |  |  | 425 |
| 4.100 |  |  | 2045 |  |  | 250 |  |  | 250 |
| 3.250 |  |  | 2046 |  |  | 450 |  |  | 450 |
| 3.950 |  |  | 2047 |  |  | 350 |  |  | 350 |
| 4.050 |  |  | 2048 |  |  | 550 |  |  | 550 |
| 4.350 |  |  | 2049 |  |  | 550 |  |  | 550 |
| 3.750 |  |  | 2050 |  |  | 300 |  |  | — |
| 3.100 |  |  | 2050 |  |  | 550 |  |  | — |
| 3.860 |  |  | 2052 |  |  | 50 |  |  | 50 |
| 4.280 |  |  | 2057 |  |  | 185 |  |  | 185 |
| 4.350 |  |  | 2064 |  |  | 250 |  |  | 250 |
| variable |  | 1 | 2069 |  |  | 76 |  |  | — |
Total first mortgage bonds |  |  |  |  |  |  | $ | 6,961 |  |  | $ | 6,335 |
Tax-exempt revenue bonds | variable |  | 2 | 2035 |  |  | 35 |  |  | 35 |
| 1.800 |  | 3 | 2049 |  |  | 75 |  |  | — |
|  |  |  |  |  | $ | 110 |  |  | $ | 35 |
Securitization bonds | 3.220 |  | 4 | 2025-2029 | 5 |  | 251 |  |  | 277 |
Revolving credit agreements | variable |  |  | 2020-2023 |  |  | — |  |  | 215 |
Total principal amount outstanding |  |  |  |  |  | $ | 7,322 |  |  | $ | 6,862 |
Current amounts |  |  |  |  |  | (202 | ) |  | (26 | )
Unamortized discounts |  |  |  |  |  | (23 | ) |  | (16 | )
Unamortized issuance costs |  |  |  |  |  | (49 | ) |  | (41 | )
Total long-term debt |  |  |  |  |  | $ | 7,048 |  |  | $ | 6,779 |
1 | The variable-rate bonds bear interest quarterly at a rate of three-month LIBOR minus 0.300 percent (1.594 percent at December 31, 2019).
2 | The interest rate on these tax‑exempt revenue bonds is reset weekly and was 1.740 percent at December 31, 2019 and 1.780 percent at December 31, 2018.
3 | The interest rate on these tax‑exempt revenue bonds will reset on October 1, 2024.
4 | The weighted-average interest rate for Consumers’ securitization bonds issued through its subsidiary, Consumers 2014 Securitization Funding, was 3.220 percent at December 31, 2019 and 3.057 percent at December 31, 2018.
5 Principal and interest payments are made semiannually.
Major Long-Term Debt Transactions | Presented in the following table is a summary of major long-term debt issuances during the year ended December 31, 2019:
| Principal (In Millions) |  | Interest Rate (%) | Issuance Date | Maturity Date
CMS Energy, parent only |  |  |  |  |
Term loan facility |  | $ | 300 |  | variable | January | December 2019
Junior subordinated notes 1 |  | 630 |  | 5.875 | February | March 2079
Term loan facility |  | 165 |  | variable | June | June 2020
Total CMS Energy, parent only |  | $ | 1,095 |  |  |  |
Consumers |  |  |  |  |
First mortgage bonds |  | $ | 300 |  | 3.750 | May | February 2050
First mortgage bonds |  | 550 |  | 3.100 | September | August 2050
First mortgage bonds |  | 76 |  | variable | September | September 2069
Tax-exempt revenue bonds |  | 75 |  | 1.800 | October | October 2049
Total Consumers |  | $ | 1,001 |  |  |  |
Total CMS Energy |  | $ | 2,096 |  |  |  |
1 These unsecured obligations rank subordinate and junior in right of payment to all of CMS Energy’s existing and future senior indebtedness. Presented in the following table is a summary of major long-term debt retirements during the year ended December 31, 2019:
| Principal (In Millions) |  | Interest Rate (%) |  | Retirement Date | Maturity Date
CMS Energy, parent only |  |  |  |  |
Term loan facility |  | $ | 300 |  | variable |  | February | December 2019
Term loan facility |  | 180 |  | variable |  | February | April 2019
Term loan facility |  | 165 |  | variable |  | August-December | June 2020
Total CMS Energy, parent only |  | $ | 645 |  |  |  |
Consumers |  |  |  |  |
First mortgage bonds |  | $ | 300 |  | 5.650 | % | May | April 2020
Total Consumers |  | $ | 300 |  |  |  |
Total CMS Energy |  | $ | 945 |  |  |  |
Debt Maturities | At December 31, 2019, the aggregate annual contractual maturities for long-term debt for the next five years were:
In Millions |
| 2020 |  | 2021 |  | 2022 |  | 2023 |  | 2024 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |
Long-term debt |  | $ | 1,111 |  |  | $ | 538 |  |  | $ | 1,354 |  |  | $ | 669 |  |  | $ | 808 |
Consumers |  |  |  |  |  |  |  |  |  |
Long-term debt |  | $ | 202 |  |  | $ | 27 |  |  | $ | 653 |  |  | $ | 354 |  |  | $ | 332 |
Presented in the following table are the minimum Palisades PPA payments included in the financing obligation:
In Millions |
December 31, 2019 |  |
2020 |  | $ | 14 |
2021 |  | 14 |
2022 |  | 3 |
Total minimum payments |  | $ | 31 |
Less discount |  | 2 |
Financing obligation |  | $ | 29 |
Less current portion |  | 13 |
Non-current portion |  | $ | 16 |
Revolving Credit Facilities | The following revolving credit facilities with banks were available at December 31, 2019:
In Millions |
Expiration Date | Amount of Facility |  | Amount Borrowed |  | Letters of Credit Outstanding |  | Amount Available |
CMS Energy, parent only |  |  |  |  |  |  |  |
June 5, 2023 1 |  | $ | 550 |  |  | $ | — |  |  | $ | 6 |  |  | $ | 544 |
CMS Enterprises, including subsidiaries |  |  |  |  |  |  |  |
September 30, 2025 2 |  | $ | 18 |  |  | $ | — |  |  | $ | 8 |  |  | $ | 10 |
Consumers 3 |  |  |  |  |  |  |  |
June 5, 2023 |  | $ | 850 |  |  | $ | — |  |  | $ | 7 |  |  | $ | 843 |
November 19, 2021 |  | 250 |  |  | — |  |  | 10 |  |  | 240 |
April 18, 2022 |  | 30 |  |  | — |  |  | 30 |  |  | — |
1 | During the year ended December 31, 2019, CMS Energy’s average borrowings totaled $5 million with a weighted-average interest rate of 3.859 percent.
2 | Under this facility, $8 million is available solely for the purpose of issuing letters of credit. Obligations under this facility are secured by the collateral accounts with the lending bank. There were no borrowings under this facility during the year ended December 31, 2019.
3 Obligations under these facilities are secured by first mortgage bonds of Consumers. During the year ended December 31, 2019, Consumers’ average borrowings totaled $2 million with a weighted-average interest rate of 3.225 percent.
Preferred Stock | Presented in the following table are details of Consumers’ preferred stock at December 31, 2019 and 2018:
| Par Value |  | Optional Redemption Price |  | Number of Shares Authorized |  | Number of Shares Outstanding |
Cumulative, with no mandatory redemption |  | $ | 100 |  |  | $ | 110 |  | 7,500,000 |  | 373,148 |

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