v3.3.0.814

Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Dec. 31, 2014
Accounting Policies [Line Items] |  |  |  |  |
Current | $ 246 |  | $ 246 |  | $ 195
Non-current | 29 |  | 29 |  | 49
Total | 275 |  | 275 |  | 244
Interest costs capitalized | 3 | $ 3 | $ 12 | $ 15 |
Treasury stock, shares, acquired |  |  | 25.4 |  |
Treasury stock, value, acquired, cost method |  |  | $ 510 |  |
Treasury stock acquired, average cost per share |  |  | $ 20.04 |  |
Adjustments related to tax withholding for share-based compensation |  |  | $ 12 |  |
Debt service |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 39 |  | 39 |  | 10
Non-current | 7 |  | 7 |  | 25
Total | 46 |  | 46 |  | 35
Rent reserve |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 0 |  | 0 |  | 4
Non-current | 0 |  | 0 |  | 0
Total | 0 |  | 0 |  | 4
Construction major maintenance |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 47 |  | 47 |  | 54
Non-current | 15 |  | 15 |  | 17
Total | 62 |  | 62 |  | 71
Security project insurance |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 159 |  | 159 |  | 127
Non-current | 5 |  | 5 |  | 5
Total | 164 |  | 164 |  | 132
Other |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Current | 1 |  | 1 |  | 0
Non-current | 2 |  | 2 |  | 2
Total | $ 3 |  | $ 3 |  | $ 2
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 |  |  | 58 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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