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Related Party Transactions - Consumers (Tables) | 12 Months Ended
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Dec. 31, 2018
Consumers Energy Company |
Related Party Transaction [Line Items] |
Schedule of Related Party Transactions, by Related Party Table | Presented in the following table is Consumers’ expense recorded from related-party transactions for the years ended December 31:
In Millions |
Description | Related Party | 2018 |  | 2017 |  | 2016 |
Purchases of capacity and energy | Affiliates of CMS Enterprises |  | $ | 83 |  |  | $ | 90 |  |  | $ | 88 |

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- Definition Tabular disclosure of related party transactions. Examples of related party transactions include, but are not limited to, transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners and (d) affiliates. + References No definition available. + Details
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