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Contingencies And Commitments (Contingencies And Commitments) (Details) (USD $)
In Millions, unless otherwise specified |
9 Months Ended | 1 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
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Sep. 30, 2013
|
Dec. 31, 2012
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Oct. 31, 2010
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Sep. 30, 2013
Consumers Energy Company [Member]
|
Dec. 31, 2012
Consumers Energy Company [Member]
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Sep. 30, 2013
NREPA [Member]
Consumers Energy Company [Member]
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Sep. 30, 2013
Superfund Liability [Member]
Consumers Energy Company [Member]
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Sep. 30, 2013
Manufactured Gas Plant [Member]
Consumers Energy Company [Member]
item
|
Dec. 31, 2011
Big Rock Decommissioning [Member]
Consumers Energy Company [Member]
|
Jul. 31, 2011
DOE Settlement [Member]
Consumers Energy Company [Member]
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|
| Regulatory Assets [Line Items] | ||||||||||
| Demand for payment by USEPA | $ 7 | |||||||||
| Cumulative environmental charge | 228 | |||||||||
| Accrual for environmental loss contingencies | 55 | 4 | 2 | 121 | ||||||
| Discounted projected costs rate | 4.34% | 2.57% | ||||||||
| Accrual for environmental loss contingencies, inflation rate | 1.00% | 2.50% | ||||||||
| Remaining undiscounted obligation amount | 73 | 131 | ||||||||
| Foreign government tax claim on sale | 142 | |||||||||
| Remediation and other response activity costs, minimum | 4 | 2 | ||||||||
| Remediation and other response activity costs. maximum | 6 | 8 | ||||||||
| Litigation settlement, gross | 120 | |||||||||
| Number of former MGPs | 23 | |||||||||
| Regulatory assets, noncurrent | $ 1,579 | $ 2,287 | $ 1,579 | $ 2,287 | $ 150 | $ 85 | ||||