v2.4.0.6

Debt (Textuals) (Details) (USD $) | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Debt Instrument [Line Items] |  |  |
Gains (Losses) on Extinguishment of Debt | $ (30,000,000) | $ (94,000,000) | $ (91,000,000)
Maximum Remaining Lease Term | 36 |  |
Lease Assets, Historical Cost | 880,000,000 | 879,000,000 |
Lease Assets, Accumulated Depreciation | 312,000,000 | 318,000,000 |
2019 First Lien Term Loan [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument Redemption Premium Percentage | 10.00% |  |
Redemption amount percentage | 103.00% |  |
Debt Instrument, Face Amount | 835,000,000 |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.50% |  |
Gains (Losses) on Extinguishment of Debt | 18,000,000 |  |
First Lien Term Loans [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Term loan interest rate spread option Federal Funds effective rate | 0.50% |  |
Term loan interest rate spread option Prime Rate | 2.25% |  |
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum | 3.25% |  |
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum | 1.25% |  |
Percentage of principal amount of Term Loan to be paid quarterly | 0.25% |  |
BRSP [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | 218,000,000 |  |
First Lien Notes 2017 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 7.25% |  |
First Lien Notes 2019 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 8.00% |  |
CCFC Notes [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount |  |  | 1,000,000,000
Debt Instrument, Interest Rate, Stated Percentage |  |  | 8.00%
Number of power plants |  |  | 6
Debt, Weighted Average Interest Rate |  | 8.90% | 8.90%
Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Percentage added to Federal Funds Effective Rate to arrive at base rate | 0.50% |  |
Repayment time for drawings under letters of credit | 2 days |  |
Excess amount of asset sales requiring mandatory prepayments | 3,000,000,000 |  |
Corporate Revolving Facility [Member] | Minimum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Applicable margin range percentage above base rate | 2.00% |  |
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates | 3.00% |  |
Unused commitment fee range percentage | 0.50% |  |
Corporate Revolving Facility [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Applicable margin range percentage above base rate | 2.25% |  |
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates | 3.25% |  |
Unused commitment fee range percentage | 0.75% |  |
CDHI [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Letter of Credit Total | 300,000,000 |  |
Cash collateralize letters of credit issued | 225,000,000 |  |
Pledged Financial Instruments, Not Separately Reported, Securities for Letter of Credit Facilities | $ 28,000,000 |  |
One Month [Member] | Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest periods for LIBOR rate borrowings | 1 month |  |
Two Months [Member] | Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest periods for LIBOR rate borrowings | 2 months |  |
Three Months [Member] | Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest periods for LIBOR rate borrowings | 3 months |  |
Six Months [Member] | Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest periods for LIBOR rate borrowings | 6 months |  |
Nine Months [Member] | Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest periods for LIBOR rate borrowings | 9 months |  |
Twelve Months [Member] | Corporate Revolving Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest periods for LIBOR rate borrowings | 12 months |  |

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