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Regulatory Matters (Tables) | 6 Months Ended
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Jun. 30, 2015
Electric Rate Case [Member] | Consumers Energy Company [Member] |
Public Utility, Property, Plant and Equipment [Line Items] |
Schedule of Requested Annual Rate Increase |
In Millions
Components of the rate increase |
Investment in rate base |  | $ | 185
Addition of natural gas-fueled electric generating plant |  |  | 35
Operating and maintenance costs |  |  | 26
Cost of capital |  |  | 21
Working capital |  |  | 6
Cost-reduction initiatives |  |  | (80)
Gross margin |  |  | (30)
Total |  | $ | 163

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- Definition Tabular disclosure of an entity's components of a requested rate increase. + References No definition available. + Details
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