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Regulatory Matters (Tables) - Consumers Energy Company | 12 Months Ended
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Dec. 31, 2018
Public Utility, Property, Plant and Equipment [Line Items] |
Schedule of Regulatory Assets and Liabilities | Presented in the following table are the regulatory assets and liabilities on Consumers’ consolidated balance sheets:
In Millions |
December 31 | End of Recovery or Refund Period | 2018 |  | 2017 |
Regulatory assets |  |  |  |  |  |
Current |  |  |  |  |  |
Energy waste reduction plan incentive 1 |  | 2019 |  | $ | 32 |  |  | $ | 18 |
Other |  | 2019 |  | 5 |  |  | 2 |
Total current regulatory assets |  |  |  | $ | 37 |  |  | $ | 20 |
Non-current |  |  |  |  |  |
Postretirement benefits 2 |  | various |  | $ | 1,028 |  |  | $ | 1,028 |
Securitized costs 3 |  | 2029 |  | 273 |  |  | 298 |
ARO 4 |  | various |  | 175 |  |  | 161 |
MGP sites 4 |  | various |  | 133 |  |  | 142 |
Unamortized loss on reacquired debt 4 |  | various |  | 68 |  |  | 53 |
Energy waste reduction plan incentive 1 |  | 2020 |  | 34 |  |  | 31 |
Energy waste reduction plan 4 |  | various |  | 26 |  |  | 39 |
Gas storage inventory adjustments 4 |  | various |  | 4 |  |  | 10 |
Other |  | various |  | 2 |  |  | 2 |
Total non-current regulatory assets |  |  |  | $ | 1,743 |  |  | $ | 1,764 |
Total regulatory assets |  |  |  | $ | 1,780 |  |  | $ | 1,784 |
Regulatory liabilities |  |  |  |  |  |
Current |  |  |  |  |  |
TCJA reserve for refund |  | 2019 |  | $ | 98 |  |  | $ | — |
Reserve for customer refunds |  | 2019 |  | 36 |  |  | 25 |
Income taxes, net |  | 2019 |  | 18 |  |  | 52 |
Other |  | 2019 |  | 3 |  |  | 3 |
Total current regulatory liabilities |  |  |  | $ | 155 |  |  | $ | 80 |
Non-current |  |  |  |  |  |
Cost of removal |  | various |  | $ | 1,966 |  |  | $ | 1,844 |
Income taxes, net |  | various |  | 1,537 |  |  | 1,564 |
Renewable energy grant |  | 2043 |  | 54 |  |  | 56 |
Renewable energy plan |  | 2028 |  | 42 |  |  | 56 |
ARO |  | various |  | 38 |  |  | 50 |
TCJA reserve for refund |  | various |  | 35 |  |  | — |
Postretirement benefits |  | various |  | — |  |  | 135 |
Other |  | various |  | 9 |  |  | 10 |
Total non-current regulatory liabilities |  |  |  | $ | 3,681 |  |  | $ | 3,715 |
Total regulatory liabilities |  |  |  | $ | 3,836 |  |  | $ | 3,795 |
1 | These regulatory assets have arisen from an alternative revenue program and are not associated with incurred costs or capital investments. Therefore, the MPSC has provided for recovery without a return.
2 | This regulatory asset is offset partially by liabilities. The net amount is included in rate base, thereby providing a return.
3 | The MPSC has authorized a specific return on this regulatory asset.
4 | These regulatory assets represent incurred costs for which the MPSC has provided, or Consumers expects, recovery without a return on investment.
Schedule of Assets and Liabilities for PSCR and GCR Underrecoveries and Overrecoveries | Presented in the following table are the assets and liabilities for PSCR and GCR underrecoveries and overrecoveries reflected on Consumers’ consolidated balance sheets:
In Millions |
December 31 | 2018 |  | 2017 |
Assets |  |  |  |
GCR underrecoveries |  | 16 |  |  | — |
Accrued gas revenue |  | $ | 16 |  |  | $ | — |
Liabilities |  |  |  |
PSCR overrecoveries |  | $ | 4 |  |  | $ | 27 |
GCR overrecoveries |  | — |  |  | 6 |
Accrued rate refunds |  | $ | 4 |  |  | $ | 33 |

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