v2.4.0.6

Commitments and Contingencies (Narrative) (Details) (USD $) Share data in Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Jul. 02, 2010
Commitments and Contingencies [Line Items] |  |  |  |
Cash collateral outstanding related to bonds | 4000000 |  |  |
Outstanding claims related to guarantees | 0 |  |  |
Royalty Expense | $ 22,000,000 | $ 25,000,000 | $ 22,000,000 |
Power generation capacity | 11,391 | 13,656 |  |
Environmental remediation liabilities related to Acquisition | 0 |  |  | 10,000,000
Amount of shares authorized to settle unsecured claims | 485 |  |  |
LTSA [Member] |  |  |  |
Unrecorded Unconditional Purchase Obligation |  |  |  |
Unrecorded Unconditional Purchase Obligation | 70,000,000 |  |  |
Term of Unrecorded Unconditional Purchase Obligation Lower Limit | 1 |  |  |
Term of Unrecorded Unconditional Purchase Obligation Upper Limit | 7 |  |  |
Public Utilities, Inventory, Fuel [Member] |  |  |  |
Unrecorded Unconditional Purchase Obligation |  |  |  |
Unrecorded Unconditional Purchase Obligation | $ 4,600,000,000 |  |  |
Term of Unrecorded Unconditional Purchase Obligation Lower Limit | 1 |  |  |
Term of Unrecorded Unconditional Purchase Obligation Upper Limit | 15 |  |  |
Term of Unrecorded Unconditional Purchase Obligation Outlier | 30 |  |  |

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- Definition Environmental remediation liabilities related to Acquisition + References No definition available. + Details
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- Definition Outstanding claims related to guarantees + References No definition available. + Details
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- Definition Power generation capacity + References No definition available. + Details
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- Definition Describes the nature of any assets held either as collateral or by third parties that, upon the occurrence of any triggering event or condition under the guarantee, the guarantor can obtain and liquidate to recover all or a portion of the amounts paid under the guarantee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 13 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 + Details
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- Definition Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 + Details
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- Definition The amount of the fixed and determinable portion of an unrecorded unconditional purchase obligation as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 47 -Paragraph 7 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308 + Details
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