XML 57 R42.htm IDEA: XBRL DOCUMENT
v3.19.1

Financings and Capitalization (Major Long-Term Debt Transactions) (Details) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2019 USD ($)
Debt Instrument [Line Items] |
Principal balance | $ 930
Debt retirement, principal | 480
CMS Energy Corporation |
Debt Instrument [Line Items] |
Principal balance | 930
Debt retirement, principal | 480
CMS Energy Corporation | Term loan facility due December 2019 |
Debt Instrument [Line Items] |
Principal balance | 300
Debt retirement, principal | $ 300
Debt issuance date | January 2019
Debt retirement date | February 2019
Maturity Date | 2019-12
CMS Energy Corporation | Junior subordinated notes 5.875% due March 2079 |
Debt Instrument [Line Items] |
Principal balance | $ 630
Interest Rate | 5.875%
Debt issuance date | February 2019
Maturity Date | 2079-03
CMS Energy Corporation | Term loan facility due April 2019 |
Debt Instrument [Line Items] |
Debt retirement, principal | $ 180
Debt retirement date | February 2019
Maturity Date | 2019-04

X
- Definition Debt Instrument Issuance Date 2 + References No definition available. + Details
Name: | cms_DebtInstrumentIssuanceDate2
Namespace Prefix: | cms_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date when the debt instrument was partially or fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.). + References No definition available. + Details
Name: | cms_DebtInstrumentRetirementDate
Namespace Prefix: | cms_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maturity date of the debt instrument. + References No definition available. + Details
Name: | cms_DebtMaturityDate
Namespace Prefix: | cms_
Data Type: | xbrli:gYearMonthItemType
Balance Type: | na
Period Type: | duration

X
- 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=114775744&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
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details
Name: | us-gaap_RepaymentsOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | srt_ConsolidatedEntitiesAxis=srt_ParentCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cms_TermLoanFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cms_JuniorSubordinatedNotesFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=cms_TermLoanFacilityOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |