v3.8.0.1

Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Accounting Policies [Line Items] |  |  |  |  |  |
Sale of Stock, Price Per Share |  | $ 15.25 |  | $ 15.25 |  |
Sale of Stock, Consideration Received on Transaction |  | $ 5,600 |  |  |  |
Payments for Merger Related Costs |  | 11 |  | $ 11 |  |
Goodwill, Beginning Balance |  |  |  | 187 |  |
Goodwill, Purchase Accounting Adjustments | [1] |  |  | 7 |  |
Goodwill, Ending Balance |  | 243 |  | 243 |  |
Current |  | 196 |  | 196 |  | $ 173
Non-current |  | 26 |  | 26 |  | 15
Total |  | 222 |  | 222 |  | 188
Interest costs capitalized |  | 7 | $ 5 | 20 | $ 14 |
Transfer of Financial Assets Accounted for as Sales, Fair Value of Derecognized Assets |  | 228 |  | 228 |  | 211
Continuing Involvement with Continued to be Recognized Transferred Financial Assets, Amount Outstanding |  | 40 |  | 40 |  | 32
Trade Receivables Sold |  |  |  | 1,600 |  |
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers |  |  |  | 1,600 |  |
Margin deposits and other prepaid expense |  | 182 |  | 182 |  | 364
Derivative assets, current | [2],[3] | 206 |  | 206 |  | 221
Total current assets |  | 2,388 |  | 2,388 |  | 2,851
Derivative Asset, Noncurrent | [2],[3] | 284 |  | 284 |  | 300
Total assets |  | 16,792 |  | 16,792 |  | 17,493
Derivative Liability, Current | [2],[3] | 113 |  | 113 |  | 138
Other current liabilities |  | 427 |  | 427 |  | 523
Total current liabilities |  | 1,794 |  | 1,794 |  | 2,205
Long-term derivative liabilities | [2],[3] | 103 |  | 103 |  | 149
Total liabilities |  | 13,469 |  | 13,469 |  | 14,154
Derivative instruments, net |  |  |  | (10) | (154) |
Other assets |  |  |  | 60 | 1 |
Accounts payable and accrued expenses |  |  |  | 95 | 53 |
Net cash provided by operating activities |  |  |  | 807 | 667 |
Debt service |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Current |  | 22 |  | 22 |  | 11
Non-current |  | 7 |  | 7 |  | 8
Total |  | 29 |  | 29 |  | 19
Construction major maintenance |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Current |  | 25 |  | 25 |  | 45
Non-current |  | 17 |  | 17 |  | 6
Total |  | 42 |  | 42 |  | 51
Security project insurance |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Current |  | 145 |  | 145 |  | 114
Non-current |  | 0 |  | 0 |  | 0
Total |  | 145 |  | 145 |  | 114
Other |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Current |  | 4 |  | 4 |  | 3
Non-current |  | 2 |  | 2 |  | 1
Total |  | 6 |  | $ 6 |  | 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 |  | 32 |  | 32 |  |
East [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Goodwill, Beginning Balance |  |  |  | 88 |  |
Goodwill, Purchase Accounting Adjustments | [1] |  |  | 8 |  |
Goodwill, Ending Balance |  | 145 |  | 145 |  |
West [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Goodwill, Beginning Balance |  |  |  | 68 |  |
Goodwill, Ending Balance |  | 66 |  | 66 |  |
Calpine Solutions [Member] | Texas [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Goodwill, Purchase Accounting Adjustments | [1] |  |  | 1 |  |
Calpine Solutions [Member] | East [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Goodwill, Purchase Accounting Adjustments |  |  |  | (9) |  |
Calpine Solutions [Member] | West [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Goodwill, Purchase Accounting Adjustments | [1] |  |  | (2) |  |
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 |  |
Goodwill, Purchase Accounting Adjustments |  |  |  | 17 |  |
North American Power [Member] | West [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Goodwill, Acquired During Period |  |  |  | 0 |  |
Scenario, Previously Reported [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Margin deposits and other prepaid expense |  |  |  |  |  | 441
Derivative assets, current |  |  |  |  |  | 1,725
Total current assets |  |  |  |  |  | 4,432
Derivative Asset, Noncurrent |  |  |  |  |  | 543
Total assets |  |  |  |  |  | 19,317
Derivative Liability, Current |  |  |  |  |  | 1,630
Other current liabilities |  |  |  |  |  | 528
Total current liabilities |  |  |  |  |  | 3,702
Long-term derivative liabilities |  |  |  |  |  | 476
Total liabilities |  |  |  |  |  | 15,978
Derivative instruments, net |  |  |  |  | (71) |
Other assets |  |  |  |  | (75) |
Accounts payable and accrued expenses |  |  |  |  | 46 |
Net cash provided by operating activities |  |  |  |  | 667 |
Restatement Adjustment [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Margin deposits and other prepaid expense |  |  |  |  |  | (77)
Derivative assets, current |  |  |  |  |  | (1,504)
Total current assets |  |  |  |  |  | (1,581)
Derivative Asset, Noncurrent |  |  |  |  |  | (243)
Total assets |  |  |  |  |  | (1,824)
Derivative Liability, Current |  |  |  |  |  | (1,492)
Other current liabilities |  |  |  |  |  | (5)
Total current liabilities |  |  |  |  |  | (1,497)
Long-term derivative liabilities |  |  |  |  |  | (327)
Total liabilities |  |  |  |  |  | $ (1,824)
Derivative instruments, net |  |  |  |  | (83) |
Other assets |  |  |  |  | 76 |
Accounts payable and accrued expenses |  |  |  |  | 7 |
Net cash provided by operating activities |  |  |  |  | $ 0 |
Revolving Credit Facility [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | 1,790 |  | 1,790 |  |
Amendment No. 6 [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | $ 1,470 |  | $ 1,470 |  |
[1] | The purchase price allocation adjustment in the East segment represents adjustments of $17 million for North American Power and $(9) million for Calpine Solutions.
[2] | At December 31, 2016, current and long-term derivative assets are shown net of collateral of $(29) million and $(3) million, respectively, and current and long-term derivative liabilities are shown net of collateral of $19 million and $85 million, respectively.
[3] | At September 30, 2017 and December 31, 2016, we had $115 million and $262 million of collateral under master netting arrangements that were not offset against our derivative instruments on the Consolidated Condensed Balance Sheets.

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