|
Commitments and Contingencies (Details Textuals) (USD $)
|
9 Months Ended |
12 Months Ended |
|
Sep. 30, 2012
years
people
kWh
weeks
employees
facilities
|
Dec. 31, 2011
|
| Loss Contingencies [Line Items] |
|
|
| Environmental Capital Expenditures Through Current Year |
|
$ 1,700,000,000 |
| Environmental Capital Expenditures in Current Year |
170,000,000 |
|
| Environmental Capital Expenditures In Future Years |
2,000,000,000 |
|
| EPA is Alleging Detroit Edison Power Plants Violated New Source Performance Standards |
5 |
|
| Possible Additional Capital Expenditures for EPA Regulations |
80,000,000 |
55,000,000 |
| Minimum Amount of Years to Incur Additional Capital Expenditures |
4 |
|
| Maximum Amount of Years to Incur Additional Capital Expenditures |
6 |
|
| Period Gas Utility Can Amortize MGP Costs |
10 |
|
| Company will Pay a Fine to the EPA to Settle Air and Water Issues |
1,750,000 |
|
| Possible Environmental Capital Expenditures to Comply with Requirements |
1,500,000 |
|
| Capital Expenditures Over the Next Few Years |
23,000,000 |
|
| Time Period to Comply with Applicable MACT Standards |
3 |
|
| Number of Defendant Oil Power and Coal Companies In Domestic District Court on Basis of Which Company Named |
24 |
|
| Number of People In Country Claiming Business Activities Contributing to Global Warming Higher Temperatures and Storm Activity |
400 |
|
| Costs Associated with Relocating Village and Unspecified Attorney's Fees and Expenses |
400,000,000 |
|
| Waiting Period of Policy |
12 |
|
| Insurance Coverage for Extra Expense when to Necessitate Power Plant when Unavailable |
490,000,000 |
|
| Period of Coverage of Policy for Extra Expenses |
3 |
|
| Primary Coverage |
500,000,000 |
|
| Coverage for Stabilization Decontamination Debris Removal Repair and Replacement of Property and Decommissioning |
2,250,000,000 |
|
| Combined Coverage Limit for Total Property Damage |
2,750,000,000 |
|
| Insurance Deductible for Nuclear Power Plant |
1,000,000 |
|
| NEIL Policies Against Terrorism Loss |
3,200,000,000 |
|
| Amount per Event Loss Associated with Nuclear Power Plants |
31,000,000 |
|
| Maintenance of Public Liability Insurance for Nuclear Power Plants |
375,000,000 |
|
| Aggregate Limit of Liabilities Arises From Terrorist Act Outside Scope of Trials Subject to One Industry |
300,000,000 |
|
| Deferred Premium Charged Levied Against Each Licensed Nuclear Facility |
117,500,000 |
|
| Limit Deferred Premium Charges Per Year |
17,500,000 |
|
| Company Obligated to Pay DOE Fee of Fermi 2 Electricity Generated and Sold |
1 |
|
| Payment from the DOE for Delaying Acceptance of Spent Nuclear Fuel |
48,000,000 |
|
| Guarantee Obligations Maximum Exposure One |
10,000,000 |
|
| Performance Bonds Outstanding |
39,000,000 |
|
| Number of Represented Employees |
5,000 |
|
| Contract Expiring for Electrical Linemen |
500 |
|
| Long-term Purchase Commitment, Amount |
5,300,000,000 |
|
| Estimated Future Capital Expenditures for Current Year |
2,100,000,000 |
|
|
Electric Utility [Member]
|
|
|
| Loss Contingencies [Line Items] |
|
|
| Number of Former MGP Sites |
3 |
|
| Accrued for Remediation Related to the Sites |
8,000,000 |
8,000,000 |
|
Gas Utility [Member]
|
|
|
| Loss Contingencies [Line Items] |
|
|
| Number of Former MGP Sites |
15 |
|
| Accrued for Remediation Related to the Sites |
38,000,000 |
36,000,000 |
|
Synthetic Fuel [Member]
|
|
|
| Loss Contingencies [Line Items] |
|
|
| Days Obligations will Survive After Expiration of All Applicable Statutes of Limitations |
90 |
|
| Guarantor Obligations, Maximum Exposure, Undiscounted |
1,200,000,000 |
|
|
Emissions [Member]
|
|
|
| Loss Contingencies [Line Items] |
|
|
| Days Obligations will Survive After Expiration of All Applicable Statutes of Limitations |
|
90 |
| Guarantor Obligations, Maximum Exposure, Undiscounted |
$ 61,000,000 |
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