|
Debt (Details 5) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | |||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2011
|
Dec. 31, 2010
|
Dec. 31, 2011
One Month [Member]
|
Dec. 31, 2011
Two Months [Member]
|
Dec. 31, 2011
Three Months [Member]
|
Dec. 31, 2011
Six Months [Member]
|
Dec. 31, 2011
Nine Months [Member]
|
Dec. 31, 2011
Twelve Months [Member]
|
Dec. 31, 2011
Minimum [Member]
|
Dec. 31, 2011
Maximum [Member]
|
Dec. 31, 2011
Corporate Revolving Facility [Member]
|
Dec. 31, 2010
Corporate Revolving Facility [Member]
|
Dec. 31, 2011
CDH [Member]
|
Dec. 31, 2010
CDH [Member]
|
Dec. 31, 2011
NDH Project Debt Credit Facility [Member]
|
Dec. 31, 2010
NDH Project Debt Credit Facility [Member]
|
Dec. 31, 2011
Various Project Financing Facilities [Member]
|
Dec. 31, 2010
Various Project Financing Facilities [Member]
|
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| Line of Credit Facility [Line Items] | ||||||||||||||||||||||||||||||
| Line of Credit Facility, Fair Value of Amount Outstanding | $ 763 | $ 711 | $ 440 | [1] | $ 443 | [1] | $ 193 | [2] | $ 165 | [2] | $ 0 | [3] | $ 34 | [3] | $ 130 | $ 69 | ||||||||||||||
| Corporate Revolving Facility Interest Details [Abstract] | ||||||||||||||||||||||||||||||
| Applicable margin range percentage above base rate | 2.00% | 2.25% | ||||||||||||||||||||||||||||
| Interest periods for LIBOR rate borrowings | 1 | 2 | 3 | 6 | 9 | 12 | ||||||||||||||||||||||||
| Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates | 3.00% | 3.25% | ||||||||||||||||||||||||||||
| Unused commitment fee range percentage | 0.50% | 0.75% | ||||||||||||||||||||||||||||
|
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