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Regulatory Matters (Schedule Of The Components Of Regulatory Assets and Liabilities) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, current | $ 37 | $ 20
Regulatory assets, noncurrent | 1,743 | 1,764
Regulatory liabilities, current | 155 | 80
Regulatory liability, noncurrent | 3,681 | 3,715
Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, current | 37 | 20
Regulatory assets, noncurrent | 1,743 | 1,764
Total regulatory assets | 1,780 | 1,784
Regulatory liabilities, current | 155 | 80
Regulatory liability, noncurrent | 3,681 | 3,715
Total regulatory liabilities | $ 3,836 | 3,795
TCJA reserve for refund | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Current regulatory liability recovery end date | 2019 |
Regulatory liabilities, current | $ 98 | 0
Regulatory liability, noncurrent | $ 35 | 0
Reserve for customer refunds | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Current regulatory liability recovery end date | 2019 |
Regulatory liabilities, current | $ 36 | 25
Income taxes, net | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Current regulatory liability recovery end date | 2019 |
Regulatory liabilities, current | $ 18 | 52
Regulatory liability, noncurrent | $ 1,537 | 1,564
Total regulatory liabilities |  | 1,600
Other | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Current regulatory liability recovery end date | 2019 |
Regulatory liabilities, current | $ 3 | 3
Regulatory liability, noncurrent | 9 | 10
Cost of removal | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory liability, noncurrent | $ 1,966 | 1,844
Renewable energy grant | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Noncurrent regulatory liability recovery end date | 2043 |
Regulatory liability, noncurrent | $ 54 | 56
Renewable energy plan | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Noncurrent regulatory liability recovery end date | 2028 |
Regulatory liability, noncurrent | $ 42 | 56
ARO | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory liability, noncurrent | 38 | 50
Postretirement benefits | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory liability, noncurrent | $ 0 | 135
Energy Waste Reduction Plan Incentive | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Current regulatory asset recovery end date | 2019 |
Regulatory assets, current | $ 32 | 18
Regulatory assets, noncurrent | $ 34 | 31
Regulatory Noncurrent Asset, End Date for Recovery | Dec. 31, 2020 |
Other | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Current regulatory asset recovery end date | 2019 |
Regulatory assets, current | $ 5 | 2
Regulatory assets, noncurrent | 2 | 2
Energy Waste Reduction Plan | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent | 26 | 39
Postretirement benefits | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent | 1,028 | 1,028
Securitized Costs | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent | $ 273 | 298
Regulatory Noncurrent Asset, End Date for Recovery | Dec. 31, 2029 |
ARO | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent | $ 175 | 161
Manufactured Gas Plant | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent |  | 142
Unamortized Loss On Reacquired Debt | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent | 68 | 53
Gas Storage Inventory Adjustments | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Regulatory assets, noncurrent | $ 4 | $ 10

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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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