v2.4.0.8

Basis of Presentation and Summary of Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Dec. 31, 2013
Accounting Policies [Line Items] |  |  |  |  |
Current | $ 244 |  | $ 244 |  | $ 203
Non-current | 42 |  | 42 |  | 69
Total | 286 |  | 286 |  | 272
Cash and cash equivalents subject to project finance facilities and lease agreements | 229 |  | 229 |  | 292
Interest Costs Capitalized | 3 | 9 | 15 | 33 |
Treasury Stock, Value, Acquired, Cost Method |  |  | 767 |  |
Adjustments Related to Tax Withholding for Share-based Compensation |  |  | 14 |  |
Debt Service |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 22 |  | 22 |  | 11
Non-current | 25 |  | 25 |  | 41
Total | 47 |  | 47 |  | 52
Rent Reserve |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 4 |  | 4 |  | 3
Non-current | 0 |  | 0 |  | 0
Total | 4 |  | 4 |  | 3
Construction Major Maintenance |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 69 |  | 69 |  | 35
Non-current | 12 |  | 12 |  | 20
Total | 81 |  | 81 |  | 55
Security Project Insurance |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 149 |  | 149 |  | 151
Non-current | 3 |  | 3 |  | 6
Total | 152 |  | 152 |  | 157
Other |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 0 |  | 0 |  | 3
Non-current | 2 |  | 2 |  | 2
Total | $ 2 |  | $ 2 |  | $ 5
Geothermal Properties, Gross [Member] | Minimum [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  |  | 13 years |  |
Geothermal Properties, Gross [Member] | Maximum [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  |  | 59 years |  |
Property, Plant and Equipment, Other Types [Member] | Minimum [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  |  | 3 years |  |
Property, Plant and Equipment, Other Types [Member] | Maximum [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  |  | 47 years |  |
Building, Machinery and Equipment, Gross [Member] | Minimum [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  |  | 3 years |  |
Building, Machinery and Equipment, Gross [Member] | Maximum [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  |  | 47 years |  |

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