v3.25.4

Income Taxes (Summary of Loss and Credit Carryforwards) (Details) $ in Millions	Dec. 31, 2025 USD ($)
Operating Loss Carryforwards [Line Items]
General business credits	$ 120
Total tax attributes	139
Consumers Energy Company
Operating Loss Carryforwards [Line Items]
General business credits	8
Total tax attributes	18
Michigan State Tax Authority
Operating Loss Carryforwards [Line Items]
Local net operating loss carryforwards	15
Michigan State Tax Authority | Consumers Energy Company
Operating Loss Carryforwards [Line Items]
Local net operating loss carryforwards	10
Arkansas State Tax Authority
Operating Loss Carryforwards [Line Items]
Local net operating loss carryforwards	2
Local Tax Authority
Operating Loss Carryforwards [Line Items]
Local net operating loss carryforwards	$ 2

X

- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards and deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

+ References

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible general business tax credit carryforwards.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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