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Plant, Property, and Equipment (Schedule Of Depreciation And Amortization) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | $ 7,953 | $ 7,360
Consumers Energy Company |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Consumers accumulated depreciation and amortization | 7,844 | 7,272
Non-utility plant assets |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | 112 | 91
Non-utility plant assets | Consumers Energy Company |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Consumers accumulated depreciation and amortization | 3 | 3
Utility plant assets |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | 7,841 | 7,269
Utility plant assets | Consumers Energy Company |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Consumers accumulated depreciation and amortization | $ 7,841 | $ 7,269

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- Definition Public Utilities, Property, Plant, and Equipment And Finance Lease Right-Of-Use Asset, Accumulated Depreciation And Amortization + References No definition available. + Details
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