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Investment Information - Narrative (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 USD ($) lots | Dec. 31, 2021 USD ($) lots
Continuous unrealized loss, qualitative disclosures: |  |
Number of positions in an unrealized loss position (lots) | lots | 9,810 | 4,700
Total number of positions (lots) | lots | 12,590 | 10,240
Largest single loss | $ | $ 7,200 | $ 1,100
Equity securities, at fair value | $ | $ 859,969 | $ 1,804,170
Equity Method Investment, Financial Statement, Reported Amounts [Abstract] |  |
Investments, time lag for reporting - low end of range | 1 month |
Investments, time lag for reporting - high end of range | 3 months |

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