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Commitment and Contingencies (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2012 | Dec. 31, 2011
Commitments and Contingencies |  |
Minimum Power Purchase Obligation |  | $ 300,000,000
Maximum DOE RD&D program contribution | 300,000,000 |
Interim RD&D funding | 44,000,000 |
Amount of application under DOE Loan Guarantee Program |  | 2,000,000,000
ACP spending reduction in October 2011 |  | 30.00%
Upper range of potential ACP asset impairment expense |  | 1,100,000,000
Estimated maximum potential severance liability |  | 14,000,000
Estimated maximum potential severance liability, DOE share |  | $ 9,000,000

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- Details
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- Definition ACP Spending Reduction in October 2011 + References No definition available. + Details
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- Definition Amount of application under DOE Loan Guarantee Program + References No definition available. + Details
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- Definition Interim RD&D funding + References No definition available. + Details
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- Definition Maximum potential severance liability + References No definition available. + Details
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- Definition Minimum Power Purchase Obligation + References No definition available. + Details
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- Definition Upper range of potential ACP asset impairment expense + References No definition available. + Details
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