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Stock-Based Compensation (Schedule Of Restricted Stock Granted) (Details) | 12 Months Ended
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Dec. 31, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 527,400
Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 504,755
Time-lapse awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 106,520
Time-lapse awards | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 101,439
Market-based awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 123,246
Market-based awards | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 118,011
Performance-based awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 123,246
Performance-based awards | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 118,011
Restricted stock units |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 13,405
Restricted stock units | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 12,800
Dividends on market-based awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 17,937
Dividends on market-based awards | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 17,152
Dividends on performance-based awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 17,505
Dividends on performance-based awards | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 16,736
Dividends on restricted stock units |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 1,669
Dividends on restricted stock units | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 1,609
Additional market-based shares based on achievement of condition |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 71,678
Additional market-based shares based on achievement of condition | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 68,857
Additional performance-based shares based on achievement of condition |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 52,194
Additional performance-based shares based on achievement of condition | Consumers Energy Company |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 50,140

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