v2.4.0.6

Debt (Textuals 1) (Details) (USD $) | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2011 | Dec. 31, 2011 | Dec. 31, 2010 | Sep. 01, 2011 | Dec. 31, 2009
Debt Instrument [Line Items] |  |  |  |  |
Number of power plants |  |  |  |  | 6
Power generation capacity |  | 11,391 | 13,656 |  |
Payments of Debt Issuance Costs |  | $ 22,000,000 |  |  |
Write off of Deferred Debt Issuance Cost |  |  | 19,000,000 |  |
Debt Disclosure [Abstract] |  |  |  |  |
Early Repayment of Senior Debt |  | 1,200,000,000 | 3,500,000,000 |  |
Repayment of Project Debt |  |  |  | 340,000,000 |
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% |  |  |
Repricing transaction premium percentage |  | 1.00% |  |  |
Days allowed to make offer to prepay |  | 30 |  |  |
Percentage of Term Loan amounts held by lenders |  | 50.00% |  |  |
Deferred Finance Costs, Gross |  | 14,000,000 |  |  |
Term Loan debt extinguishment costs | 74,000,000 | 5,000,000 |  |  |
Write-off amount of unamortized deferred financing costs | 36,000,000 |  |  |  |
Write-off amount of debt discount | 25,000,000 |  |  |  |
Subsidiary Project Debt prepayment premiums | 13,000,000 |  |  |  |
Back-Stopped Letters of Credit |  | 83,000,000 |  |  |
Percentage added to Federal Funds Effective Rate to arrive at base rate |  | 0.50% |  |  |
Repayment time for drawings under letters of credit |  | 2 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | 1,000,000,000 |  |  |
Equity Method Investment, Ownership Percentage |  | 50.00% |  |  |
Excess amount of asset sales requiring mandatory prepayments |  | 3,000,000,000 |  |  |
CDHI Letter of Credit Facility Total |  | 200,000,000 |  |  |
CDHI Upsize Facility Total |  | $ 300,000,000 |  |  |
Debt, Weighted Average Interest Rate |  | 8.90% | 8.90% |  |
Minimum [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
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% |  |  |
Maximum [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
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% |  |  |
One Month [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
Interest periods for LIBOR rate borrowings |  | 1 |  |  |
Two Months [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
Interest periods for LIBOR rate borrowings |  | 2 |  |  |
Three Months [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
Interest periods for LIBOR rate borrowings |  | 3 |  |  |
Six Months [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
Interest periods for LIBOR rate borrowings |  | 6 |  |  |
Nine Months [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
Interest periods for LIBOR rate borrowings |  | 9 |  |  |
Twelve Months [Member] |  |  |  |  |
Debt Disclosure [Abstract] |  |  |  |  |
Interest periods for LIBOR rate borrowings |  | 12 |  |  |

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- Definition For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399 + Details
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