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Fair Value of Financial Instruments (Tables) | 3 Months Ended
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Mar. 31, 2014
Financial Instruments, Owned, at Fair Value [Abstract] |
Estimated Fair Values of Financial Instruments | The following table presents the estimated fair values of financial instruments at March 31, 2014 and December 31, 2013.
| March 31, 2014 |  | December 31, 2013
| (Amounts in thousands)
Assets |  |  |
Investments | $ | 3,316,704 |  |  | $ | 3,158,312 |
Total return swaps | $ | 1,499 |  |  | $ | 1,650 |
Liabilities |  |  |
Equity contracts | $ | 426 |  |  | $ | 140 |
Secured notes | $ | 140,000 |  |  | $ | 140,000 |
Unsecured note | $ | 130,000 |  |  | $ | 50,000 |

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