v2.4.0.6

Summary of Significant Accounting Policies (Tables) | 3 Months Ended
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Mar. 31, 2013
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment [Table Text Block] | Property, Plant and Equipment, Net — At March 31, 2013 and December 31, 2012, the components of property, plant and equipment are stated at cost less accumulated depreciation as follows (in millions):
| March 31, 2013 |  | December 31, 2012 |  | Depreciable Lives
Buildings, machinery and equipment | $ | 14,783 |  |  | $ | 14,774 |  |  | 3 – 47 Years
Geothermal properties | 1,248 |  |  | 1,243 |  |  | 13 – 59 Years
Other | 155 |  |  | 142 |  |  | 3 – 47 Years
| 16,186 |  |  | 16,159 |  |  |
Less: Accumulated depreciation | 4,516 |  |  | 4,390 |  |  |
| 11,670 |  |  | 11,769 |  |  |
Land | 98 |  |  | 98 |  |  |
Construction in progress | 1,284 |  |  | 1,138 |  |  |
Property, plant and equipment, net | $ | 13,052 |  |  | $ | 13,005 |  |  |
Schedule of Components of Restricted Cash | The table below represents the components of our restricted cash as of March 31, 2013 and December 31, 2012 (in millions):
| March 31, 2013 |  | December 31, 2012
| Current |  | Non-Current |  | Total |  | Current |  | Non-Current |  | Total
Debt service(1) | $ | 11 |  |  | $ | 41 |  |  | $ | 52 |  |  | $ | 11 |  |  | $ | 41 |  |  | $ | 52 |
Rent reserve | 3 |  |  | — |  |  | 3 |  |  | — |  |  | — |  |  | — |
Construction/major maintenance | 30 |  |  | 10 |  |  | 40 |  |  | 32 |  |  | 14 |  |  | 46 |
Security/project/insurance | 69 |  |  | 3 |  |  | 72 |  |  | 101 |  |  | 3 |  |  | 104 |
Other | 29 |  |  | 3 |  |  | 32 |  |  | 49 |  |  | 2 |  |  | 51 |
Total | $ | 142 |  |  | $ | 57 |  |  | $ | 199 |  |  | $ | 193 |  |  | $ | 60 |  |  | $ | 253 |
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(1) | At March 31, 2013 and December 31, 2012, amounts restricted for debt service included approximately $24 million and $25 million, respectively, of repurchase agreements with a financial institution containing maturity dates greater than one year.

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- Definition Tabular disclosure of the useful life and salvage value of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -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 FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Tabular disclosure of the cash and cash items which are restricted as to withdrawal or usage. The provisions of any restrictions are described in a note to the financial statements. 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 -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 4: 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 + Details
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