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Contingencies And Commitments (European Commission Matters) (Narrative) (Details) In Millions, unless otherwise specified | 1 Months Ended | 12 Months Ended | 1 Months Ended |  |  | 1 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jan. 31, 2007 | Dec. 31, 2011 | Jul. 31, 2006 Italian Government [Member] | Nov. 19, 2009 Italian Government [Member] USD ($) | Jan. 31, 2007 Tariffs Granted By Spain [Member] USD ($) | Jan. 31, 2007 Tariffs Granted By Spain [Member] EUR (€) | Jan. 31, 2007 Spanish Government [Member]
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Number of years operating under a power supply structure |  |  | 10 |  |  |  | 9
Italian government extended tariff charge, minimum |  |  |  | $ 300 |  |  |
Italian government extended tariff charge, maximum |  |  |  | 500 |  |  |
Charge related to EC announcement |  |  |  | 250 |  |  |
Write-off of receivable |  |  |  | 20 |  |  |
Days provided to submit observations and comments to the EC | 30 |  |  |  |  |  |
Amount of curtailment, in kmt-per year |  | 44 |  |  |  |  |
Current agreement expiration date |  | 2012 |  |  |  |  |
Loss contingency, range of possible loss, maximum |  |  |  |  | $ 90 | € 70 |

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