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Contingencies and Commitments (Schedule of Remediation and Other Response Activity Costs by Year) (Details) $ in Millions | Mar. 31, 2024 USD ($)
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Bay Harbor |
Site Contingency [Line Items] |
2024 | $ 3
2025 | 4
2026 | 4
2027 | 4
2028 | 4
2029 | 4
Consumers Energy Company | MGP sites |
Site Contingency [Line Items] |
2024 | 2
2025 | 1
2026 | 7
2027 | 10
2028 | 25
2029 | $ 7

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