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Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2009
Related Party Transactions [Abstract] |  |
Voting interests of the Company | 10.00% |
Executed surety bonds to guarantee payment obligations | 5 |
Outstanding exposure on surety bonds | $ 340 |
Invested in the MIPS Fund |  | 25
Earned from investment in MIPS Fund |  | $ 0.2

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- Definition Earnings from municipal bond inflation protection fund. + References No definition available. + Details
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- Definition Invested in Municipal Bond Inflation Protection Fund. + References No definition available. + Details
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- Definition Number of executed surety bonds to guarantee payment obligations. + References No definition available. + Details
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- Definition Outstanding exposure on surety bonds. + References No definition available. + Details
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- Definition Percentage of voting interests of the Company. + References No definition available. + Details
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- Details
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