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Obligations Under Investment Agreements | 12 Months Ended
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Dec. 31, 2011
Obligations Under Investment Agreements [Abstract] |
Obligations Under Investment Agreements | 13 OBLIGATIONS UNDER INVESTMENT AGREEMENTS Obligations under investment agreements, including those structured in the form of repurchase agreements, are recorded on a settlement-date basis. Certain investment agreements have contractual provisions that allow our counterparty the flexibility to withdraw funds prior to the legal maturity date. Amounts included in the table below are based on the earliest optional draw date. As of December 31, 2011 and 2010, the contractual interest rates for these agreements, which include both fixed and variable, ranged from 0.40% to 6.11% and from 0.17% to 6.37%, respectively. As of December 31, 2011 and 2010, obligations under investment agreements were $546,546 and $805,632, respectively. Net payments due under investment agreements, based on the earliest optional draw date, in each of the next five years ending December 31, and the periods thereafter, are as follows:
|  | Principal Amount |
2012 |  | $ | 254,749 |
2013 |  |  | 19,464 |
2014 |  |  | 99,230 |
2015 |  |  | — |
2016 |  |  | — |
All later years |  |  | 173,103 |
|  | $ | 546,546 |

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- Definition Obligations under investment agreements [Text Block]. + References No definition available. + Details
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