Contingencies and Commitments (Schedule of Contractual Purchase Obligations) (Details) $ in Millions	Dec. 31, 2025 USD ($)
Guarantees And Other Contingencies [Line Items]
Total	$ 20,565
2026	2,384
2027	1,666
2028	1,398
2029	1,333
2030	1,314
2030	12,470
Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	19,683
2026	2,058
2027	1,503
2028	1,293
2029	1,208
2030	1,243
2030	12,378
Total PPAs
Guarantees And Other Contingencies [Line Items]
Total	16,983
2026	873
2027	904
2028	930
2029	942
2030	1,011
2030	12,323
Total PPAs \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	16,983
2026	873
2027	904
2028	930
2029	942
2030	1,011
2030	12,323
Other
Guarantees And Other Contingencies [Line Items]
Total	3,582
2026	1,511
2027	762
2028	468
2029	391
2030	303
2030	147
Other \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	2,700
2026	1,185
2027	599
2028	363
2029	266
2030	232
2030	55
MCV PPA \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	5,539
2026	339
2027	312
2028	316
2029	308
2030	395
2030	3,869
Related-party PPAs \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	62
2026	32
2027	30
2028	0
2029	0
2030	0
2030	0
Other PPAs \| Consumers Energy Company
Guarantees And Other Contingencies [Line Items]
Total	11,382
2026	502
2027	562
2028	614
2029	634
2030	616
2030	$ 8,454

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Includes, but is not limited to, lease not yet commenced.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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+ References

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+ References

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+ References

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+ References

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Amount of unrecorded obligation to transfer funds in future for fixed or minimum amount or quantity of product and service at fixed or minimum price. Includes, but is not limited to, lease not yet commenced and take-or-pay and throughput contracts.

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 440
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482648/440-10-50-4

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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