v2.4.0.6

Summary of Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2013 | Mar. 31, 2012 | Dec. 31, 2012
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Held-to-maturity Securities, Restricted | $ 24 |  | $ 25
Current | 142 |  | 193
Non-current | 57 |  | 60
Total | 199 |  | 253
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Cash and cash equivalents subject to project finance facilities and lease agreements | 176 |  | 131
Interest Costs Capitalized | 12 | 8 |
Inventory | 299 |  | 301
Treasury Stock, Value, Acquired, Cost Method | 75 |  |
Adjustments Related to Tax Withholding for Share-based Compensation | 6 |  |
Debt Service |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Current | 11 |  | 11
Non-current | 41 |  | 41
Total | 52 |  | 52
Rent Reserve |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Current | 3 |  | 0
Non-current | 0 |  | 0
Total | 3 |  | 0
Construction Major Maintenance |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Current | 30 |  | 32
Non-current | 10 |  | 14
Total | 40 |  | 46
Security Project Insurance |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Current | 69 |  | 101
Non-current | 3 |  | 3
Total | 72 |  | 104
Other |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Current | 29 |  | 49
Non-current | 3 |  | 2
Total | 32 |  | 51
Geothermal Properties, Gross [Member] | Minimum [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Property, Plant and Equipment, Estimated Useful Lives | 13 years |  |
Geothermal Properties, Gross [Member] | Maximum [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Property, Plant and Equipment, Estimated Useful Lives | 59 years |  |
Property, Plant and Equipment, Other Types [Member] | Minimum [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Property, Plant and Equipment, Estimated Useful Lives | 3 years |  |
Property, Plant and Equipment, Other Types [Member] | Maximum [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Property, Plant and Equipment, Estimated Useful Lives | 47 years |  |
Building, Machinery and Equipment, Gross [Member] | Minimum [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Property, Plant and Equipment, Estimated Useful Lives | 3 years |  |
Building, Machinery and Equipment, Gross [Member] | Maximum [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Property, Plant and Equipment, Estimated Useful Lives | 47 years |  |
Income Statement [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Prior Period Reclassification Adjustment |  | 3 |
Cash Flow Statement [Member] |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |
Prior Period Reclassification Adjustment |  | $ 4 |

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- Definition The carrying amount of securities categorized as held-to-maturity which serve as security for borrowings or other arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 5 -Paragraph 18, 19 -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 AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph i -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph b -Article 4 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Section 563c.102 -Paragraph 4 -Chapter V -Subsection I -LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.6) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5086-111524 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 6 -Article 9 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX210.4-08(b)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 + Details
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- Definition Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6386567&loc=d3e3927-108312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6676-107765 + Details
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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 80 -Subparagraph Exhibit 4-8, 3 -IssueDate 2006-05-01 -Chapter 4 -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 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 + Details
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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 80 -Subparagraph Exhibit 4-8, 3 -IssueDate 2006-05-01 -Chapter 4 -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 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 + Details
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