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Contingencies And Commitments (Tables) | 6 Months Ended
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Jun. 30, 2018
Site Contingency [Line Items] |
Guarantees | Presented in the following table are CMS Energy’s and Consumers’ guarantees at June 30, 2018:
In Millions |
Guarantee Description | Issue Date | Expiration Date | Maximum Obligation |  | Carrying Amount |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Indemnity obligations from stock and asset sale agreements 1 |  | Various |  | Indefinite |  | $ | 153 |  |  | $ | 3 |
Guarantees 2 |  | Various |  | Indefinite |  | 39 |  |  | — |
Consumers |  |  |  |  |  |  |  |
Guarantee 2 |  | July 2011 |  | Indefinite |  | $ | 30 |  |  | $ | — |
1 | These obligations arose from stock and asset sale agreements under which CMS Energy or a subsidiary of CMS Energy indemnified the purchaser for losses resulting from various matters, primarily claims related to taxes. CMS Energy believes the likelihood of material loss to be remote for the indemnity obligations not recorded as liabilities.
2 | At Consumers, this obligation comprises a guarantee provided to the U.S. Department of Energy in connection with a settlement agreement regarding damages resulting from the department’s failure to accept spent nuclear fuel from nuclear power plants formerly owned by Consumers. At CMS Energy, the guarantee obligations comprise Consumers’ guarantee to the U.S. Department of Energy and CMS Energy’s 1994 guarantee of non‑recourse revenue bonds issued by Genesee.
Consumers Energy Company |
Site Contingency [Line Items] |
Guarantees | Presented in the following table are CMS Energy’s and Consumers’ guarantees at June 30, 2018:
In Millions |
Guarantee Description | Issue Date | Expiration Date | Maximum Obligation |  | Carrying Amount |
CMS Energy, including Consumers |  |  |  |  |  |  |  |
Indemnity obligations from stock and asset sale agreements 1 |  | Various |  | Indefinite |  | $ | 153 |  |  | $ | 3 |
Guarantees 2 |  | Various |  | Indefinite |  | 39 |  |  | — |
Consumers |  |  |  |  |  |  |  |
Guarantee 2 |  | July 2011 |  | Indefinite |  | $ | 30 |  |  | $ | — |
1 | These obligations arose from stock and asset sale agreements under which CMS Energy or a subsidiary of CMS Energy indemnified the purchaser for losses resulting from various matters, primarily claims related to taxes. CMS Energy believes the likelihood of material loss to be remote for the indemnity obligations not recorded as liabilities.
2 | At Consumers, this obligation comprises a guarantee provided to the U.S. Department of Energy in connection with a settlement agreement regarding damages resulting from the department’s failure to accept spent nuclear fuel from nuclear power plants formerly owned by Consumers. At CMS Energy, the guarantee obligations comprise Consumers’ guarantee to the U.S. Department of Energy and CMS Energy’s 1994 guarantee of non‑recourse revenue bonds issued by Genesee.
Bay Harbor |
Site Contingency [Line Items] |
Expected Remediation Cost By Year | CMS Energy expects to pay the following amounts for long-term liquid disposal and operating and maintenance costs during the remainder of 2018 and in each of the next five years:
In Millions |
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
CMS Energy |  |  |  |  |  |  |  |  |  |  |  |
Long-term liquid disposal and operating and maintenance costs |  | $ | 2 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |  |  | $ | 4 |
Gas Utility | Manufactured Gas Plant | Consumers Energy Company |
Site Contingency [Line Items] |
Expected Remediation Cost By Year |
In Millions |
| 2018 |  | 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |
Consumers |  |  |  |  |  |  |  |  |  |  |  |
Remediation and other response activity costs |  | $ | 11 |  |  | $ | 18 |  |  | $ | 10 |  |  | $ | 18 |  |  | $ | 7 |  |  | $ | 2 |

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- Definition Tabular disclosure of each guarantee obligation, or each group of similar guarantee obligations, including (a) the nature of the guarantee, including its term, how it arose, and the events or circumstances that would require the guarantor to perform under the guarantee; (b) the maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee; (c) the current carrying amount of the liability, if any, for the guarantor's obligations under the guarantee; and (d) the nature of any recourse provisions under the guarantee, and any assets held either as collateral or by third parties, and any relevant related party disclosure. Excludes disclosures about product warranties. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12265-110248 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248 + Details
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