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Obligations under Investment Agreements (Tables) | 12 Months Ended
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Dec. 31, 2012
Principal Due under Investment and Investment Repurchase Agreements, Based on Expected Optional Draw Date | Principal due under investment and investment repurchase agreements, based on the expected optional draw date, in each of the next five years ending December 31, and the periods thereafter, are as follows:
|  | Principal Amount |
2013 |  | $ | 5,926 |
2014 |  |  | 190,000 |
2015 |  |  | 44,343 |
2016 |  |  | 4,002 |
2017 |  |  | 117,833 |
All later years |  |  | — |
|  | $ | 362,104 |

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- Definition Expected Principal Payments Due Under Investment Agreements Table [Text Block] + References No definition available. + Details
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