Debt Instrument, Interest Rate Floor

No definition available.

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- Definition

Debt Instrument, Interest Rate Reset Term

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Financings and Capitalization (Major Long-Term Debt Transactions) (Details) - USD ($)	1 Months Ended	9 Months Ended
	Oct. 29, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Principal balance		$ 2,334,000,000
Consumers Energy Company
Debt Instrument [Line Items]
Principal balance		1,534,000,000
First Mortgage Bonds Due August 2051 \| Consumers Energy Company
Debt Instrument [Line Items]
Principal balance		$ 575,000,000
Interest Rate		3.50%
First Mortgage Bonds Due May 2060 \| Consumers Energy Company
Debt Instrument [Line Items]
Principal balance		$ 525,000,000
Interest Rate		2.50%
First Mortgage Bonds Due May 2070 \| Consumers Energy Company
Debt Instrument [Line Items]
Principal balance		$ 134,000,000
Effective interest rate		0.00%
CMS Energy Corporation
Debt Instrument [Line Items]
Principal balance		$ 800,000,000
CMS Energy Corporation \| Junior subordinated notes
Debt Instrument [Line Items]
Principal balance		$ 500,000,000
Interest Rate		4.75%
Debt instrument interest rate reset term		5 years
London Interbank Offered Rate (LIBOR) \| First Mortgage Bonds Due May 2070 \| Consumers Energy Company
Debt Instrument [Line Items]
Basis spread on variable rate		0.30%
Interest rate floor		0.00%
Five-year Treasury Rate \| CMS Energy Corporation \| Junior subordinated notes
Debt Instrument [Line Items]
Basis spread on variable rate		4.116%
Term Loan Facility Due February 2021 \| CMS Energy Corporation \| Term loan facility
Debt Instrument [Line Items]
Principal balance		$ 300,000,000
Effective interest rate		0.606%
Term Loan Facility Due February 2021 \| London Interbank Offered Rate (LIBOR) \| CMS Energy Corporation \| Term loan facility
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Term loan facility due January 2021 \| Term loan facility \| Consumers Energy Company
Debt Instrument [Line Items]
Principal balance		$ 300,000,000
Effective interest rate		0.556%
Term loan facility due January 2021 \| London Interbank Offered Rate (LIBOR) \| Term loan facility
Debt Instrument [Line Items]
Basis spread on variable rate		0.45%
Subsequent Event \| First Mortgage Bonds Due October 2070 \| Consumers Energy Company
Debt Instrument [Line Items]
Principal balance	$ 127,000,000
Subsequent Event \| London Interbank Offered Rate (LIBOR) \| First Mortgage Bonds Due October 2070 \| Consumers Energy Company
Debt Instrument [Line Items]
Basis spread on variable rate	0.30%
Interest rate floor	0.00%