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Public Utilities, Deferred Information Technology Development Costs

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Public Utilities, Operating and Maintenance Costs

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Public Utilities, Surcharge For Recovery Of Excess Distribution Investments

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Public Utility Regulatory Filing, Service Restoration Cost Deferral Requested Amount

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Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved return on equity.

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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.

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Amount of public utility's amended requested rate increase (decrease) with regulatory agency.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested return on equity.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Regulatory Matters (Details) - USD ($) $ in Millions	1 Months Ended				3 Months Ended			9 Months Ended		16 Months Ended
Regulatory Matters (Details) - USD ($) $ in Millions	Jul. 31, 2026	Apr. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Aug. 20, 2025	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026
Public Utilities, General Disclosures [Line Items]
Operating Revenue					$ 2,183	$ 2,021		$ 6,742	$ 6,306
Consumers Energy Company
Public Utilities, General Disclosures [Line Items]
Operating Revenue					2,038	$ 1,913		6,376	$ 6,007
Consumers Energy Company \| Service restoration cost deferral
Public Utilities, General Disclosures [Line Items]
Public utility filing with the MPSC					$ 57			$ 57		$ 57
Consumers Energy Company \| J.H. Campbell Generating Units
Public Utilities, General Disclosures [Line Items]
Financial impact of emergency order	$ 97						$ 42			303
Operating Revenue	$ 144						$ 78			$ 344
2025 Electric Rate Case
Public Utilities, General Disclosures [Line Items]
Amended requested annual rate increase				$ 387
2025 Electric Rate Case \| Consumers Energy Company
Public Utilities, General Disclosures [Line Items]
Requested annual rate increase				$ 423
Requested annual rate increase, as a percent				10.25%
Public utilities operating and maintenance costs			$ 22	$ 21
Public utilities deferred information technology development costs			15	15
Amended requested annual rate increase		$ 328
Surcharge for the recovery of excess distribution investments			24	$ 24
Additional annual rate increase authorized			$ 277
Rate of return on equity authorized			9.90%
Ordered rate amendment			$ 217