Cash and Cash Equivalents (Schedule Of Cash And Cash Equivalents, Including Restricted Amounts) (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
Sep. 30, 2025 |
Dec. 31, 2024 |
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| Cash and Cash Equivalents [Line Items] | ||||
| Cash and cash equivalents | $ 451 | $ 509 | ||
| Restricted cash and cash equivalents | 102 | 106 | ||
| Current assets held for sale | 26 | 0 | ||
| Cash and cash equivalents, including restricted amounts | 579 | 615 | $ 432 | $ 178 |
| Consumers Energy Company | ||||
| Cash and Cash Equivalents [Line Items] | ||||
| Cash and cash equivalents | 257 | 25 | ||
| Restricted cash and cash equivalents | 68 | 86 | ||
| Cash and cash equivalents, including restricted amounts | $ 325 | $ 111 | $ 311 | $ 119 |
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- Definition Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; attributable to continuing operation. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount classified as cash and cash equivalents attributable to disposal group held for sale or disposed of. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash and cash equivalent restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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