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Plant, Property, and Equipment (Schedule Of Depreciation And Amortization) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | $ 7,037 | $ 6,510
Consumers Energy Company |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | 6,958 | 6,441
Utility plant assets |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | 6,956 | 6,439
Utility plant assets | Consumers Energy Company |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | 6,956 | 6,439
Non-utility plant assets |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | 81 | 71
Non-utility plant assets | Consumers Energy Company |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |
Accumulated depreciation and amortization | $ 2 | $ 2

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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.14) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Period end book value of accumulated depreciation on property, plant and equipment (PPE) that is owned by the regulated operations of the public utility. + References No definition available. + Details
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