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Financial Instruments (Tables) | 9 Months Ended
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Sep. 30, 2023
Fair Value Disclosures [Abstract] |
Estimated Fair Values of Financial Instruments | The following table presents the fair values of financial instruments:
| September 30, 2023 |  | December 31, 2022
| (Amounts in thousands)
Assets |  |  |
Investments | $ | 4,997,428 |  |  | $ | 4,910,800 |
Note receivable | 9,888 |  |  | — |
Liabilities |  |  |
Options sold | 512 |  |  | 162 |
Notes payable | 549,539 |  |  | 375,631 |

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