Derivative Instruments - Schedule of Gain (Loss) Recognized in Consolidated Statements of Operations Related to Principal Derivative Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ (80,705)	$ (188,539)	$ (37,444)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net foreign exchange gains (losses), Net realized and unrealized gains (losses) on investments	Net foreign exchange gains (losses), Net realized and unrealized gains (losses) on investments	Net foreign exchange gains (losses), Net realized and unrealized gains (losses) on investments
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ (80,910)	$ (195,005)	$ (32,909)
Interest rate futures \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	3,877	(86,863)	(15,846)
Interest rate swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	0	0	(1,184)
Foreign currency forward contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(877)	(51,401)	(19,151)
Foreign currency forward contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(11,761)	21,689	(1,521)
Foreign currency forward contracts \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Accumulated other comprehensive income (loss)	205	6,466	(4,535)
Credit default swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(70,924)	(9,084)	3,479
Total return swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	0	(6)	1,314
Equity futures \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(1,928)	(69,972)	0
Warrants \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	0	632	0
Commodity options \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(4,553)	0	0
Commodity futures \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ 5,256	$ 0	$ 0

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4E

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (a)
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

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