v3.7.0.1

Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016 | Dec. 31, 2016
Accounting Policies [Line Items] |  |  |
Goodwill, Beginning Balance | $ 187 |  |
Goodwill, Ending Balance | 233 |  |
Current | 162 |  | $ 173
Non-current | 15 |  | 15
Total | 177 |  | 188
Interest costs capitalized | 7 | $ 4 |
Transfer of Financial Assets Accounted for as Sales, Fair Value of Derecognized Assets | 179 |  | 211
Continuing Involvement with Continued to be Recognized Transferred Financial Assets, Amount Outstanding | 40 |  | 32
Trade Receivables Sold | 542 |  |
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers | 546 |  |
Debt service |  |  |
Accounting Policies [Line Items] |  |  |
Current | 12 |  | 11
Non-current | 7 |  | 8
Total | 19 |  | 19
Construction major maintenance |  |  |
Accounting Policies [Line Items] |  |  |
Current | 48 |  | 45
Non-current | 6 |  | 6
Total | 54 |  | 51
Security project insurance |  |  |
Accounting Policies [Line Items] |  |  |
Current | 99 |  | 114
Non-current | 0 |  | 0
Total | 99 |  | 114
Other |  |  |
Accounting Policies [Line Items] |  |  |
Current | 3 |  | 3
Non-current | 2 |  | 1
Total | $ 5 |  | $ 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 |  |
Texas [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Beginning Balance | $ 31 |  |
Goodwill, Ending Balance | 31 |  |
East [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Beginning Balance | 88 |  |
Goodwill, Ending Balance | 135 |  |
West [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Beginning Balance | 68 |  |
Goodwill, Ending Balance | 67 |  |
Calpine Solutions [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Purchase Accounting Adjustments | (3) |  |
Calpine Solutions [Member] | Texas [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Purchase Accounting Adjustments | 0 |  |
Calpine Solutions [Member] | East [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Purchase Accounting Adjustments | (2) |  |
Calpine Solutions [Member] | West [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Purchase Accounting Adjustments | (1) |  |
North American Power [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Acquired During Period | 49 |  |
North American Power [Member] | Texas [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Acquired During Period | 0 |  |
North American Power [Member] | East [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Acquired During Period | 49 |  |
North American Power [Member] | West [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Goodwill, Acquired During Period | $ 0 |  |

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