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Financings And Capitalization (Major Long-Term Debt Transactions) (Details) - CMS Energy [Member] | 6 Months Ended
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Jun. 30, 2016 USD ($)
Debt Instrument [Line Items] |
Principal Balance | $ 300,000,000
Senior Notes 3.000% Due May 2026 [Member] |
Debt Instrument [Line Items] |
Principal Balance | $ 300,000,000
Interest rate | 3.00%
Debt issuance date | May 2016
Maturity date | May 2026

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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