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Financial Instruments (Tables) | 3 Months Ended
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Mar. 31, 2022
Financial Instruments, Owned, at Fair Value [Abstract] |
Estimated Fair Values of Financial Instruments | The following table presents the fair values of financial instruments:
| March 31, 2022 |  | December 31, 2021
| (Amounts in thousands)
Assets |  |  |
Investments | $ | 5,039,614 |  |  | $ | 5,142,589 |
Liabilities |  |  |
Options sold | 569 |  |  | 301 |
Notes payable | 384,743 |  |  | 413,378 |

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