v3.4.0.3

Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015 | Dec. 31, 2015
Accounting Policies [Line Items] |  |  |
Prior Period Reclassification Adjustment |  |  | $ 152
Current | $ 167 |  | 216
Non-current | 17 |  | 12
Total | 184 |  | 228
Interest costs capitalized | 4 | $ 5 |
Debt service |  |  |
Accounting Policies [Line Items] |  |  |
Current | 29 |  | 28
Non-current | 7 |  | 8
Total | 36 |  | 36
Construction major maintenance |  |  |
Accounting Policies [Line Items] |  |  |
Current | 45 |  | 50
Non-current | 7 |  | 2
Total | 52 |  | 52
Security project insurance |  |  |
Accounting Policies [Line Items] |  |  |
Current | 91 |  | 136
Non-current | 1 |  | 0
Total | 92 |  | 136
Other |  |  |
Accounting Policies [Line Items] |  |  |
Current | 2 |  | 2
Non-current | 2 |  | 2
Total | $ 4 |  | $ 4
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 | 46 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 | 46 years |  |

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- Definition Amount of interest capitalized during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Allowance for Funds Used during Construction -URI http://asc.fasb.org/extlink&oid=6504829 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 + Details
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