v3.25.4

Schedule II - Valuation and Qualifying Accounts and Reserves (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Allowance for uncollectible accounts |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | $ 23 | $ 21 | $ 27
Charged to Expense | 40 | 33 | 34
Charged to Other Accounts | 0 | 0 | 0
Deductions | 36 | 31 | 40
Balance at End of Period | 27 | 23 | 21
Allowance for uncollectible accounts | Consumers Energy Company |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 23 | 21 | 27
Charged to Expense | 40 | 33 | 34
Charged to Other Accounts | 0 | 0 | 0
Deductions | 36 | 31 | 40
Balance at End of Period | 27 | 23 | 21
Deferred tax valuation allowance |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 1 | 2 | 2
Charged to Expense | 1 | 0 | 0
Charged to Other Accounts | 0 | 0 | 0
Deductions | 0 | 1 | 0
Balance at End of Period | $ 2 | $ 1 | $ 2

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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column B)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column E)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4 + Details
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