v2.3.0.11

Debt (Details 2) (USD $) In Millions, unless otherwise specified | 6 Months Ended |  |  |  |  |  |  |  |  | 6 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2011 | Jun. 30, 2011 Corporate Revolving Facility | Dec. 31, 2010 Corporate Revolving Facility | Jun. 30, 2011 Calpine Development Holdings, Inc. | Dec. 31, 2010 Calpine Development Holdings, Inc. | Jun. 30, 2011 NDH Project Debt credit facility | Dec. 31, 2010 NDH Project Debt credit facility | Jun. 30, 2011 Various project financing facilities | Dec. 31, 2010 Various project financing facilities | Jun. 30, 2011 Minimum | Jun. 30, 2011 Maximum | Jun. 30, 2011 One Month | Jun. 30, 2011 Two Months | Jun. 30, 2011 Three Months | Jun. 30, 2011 Six Months | Jun. 30, 2011 Nine Months | Jun. 30, 2011 Twelve Months
Amounts issued under letter of credit facilities [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of amounts outstanding |  | $ 369 | [1] | $ 443 | [1] | $ 193 | $ 165 |  | [2] | $ 34 | [2] | $ 100 | $ 69 |  |  |  |  |  |  |  |
Corporate Revolving Facility Interest Details [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable margin range percentage above base rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00% | 2.25% |  |  |  |  |  |
Percentage added to Federal Funds Effective Rate to arrive at base rate | 0.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest periods for LIBOR rate borrowings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 | 2 | 3 | 6 | 9 | 12
Applicable margin range percentage added to the British Bankers' Association Interest Settlement Rates |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% | 3.25% |  |  |  |  |  |
Unused commitment fee range percentage |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.50% | 0.75% |  |  |  |  |  |
[1] | When we entered into our $1.0 billion Corporate Revolving Facility on December 10, 2010, the letters of credit issued under our First Lien Credit Facility were either replaced with letters of credit issued by our Corporate Revolving Facility or back-stopped by an irrevocable standby letter of credit issued by a third-party. Our letters of credit under our Corporate Revolving Facility at December 31, 2010 include those that were back-stopped of approximately $83 million. The back-stopped letters of credit were returned and extinguished during the first quarter of 2011.
[2] | We repaid and terminated the NDH Project Debt on March 9, 2011.

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