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, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ (188,539)	$ (37,444)	$ 100,152
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	$ (195,005)	$ (32,909)	$ 88,467
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	6,466	(4,535)	11,685
Interest rate futures \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(86,863)	(15,846)	103,102
Interest rate swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	0	(1,184)	2,334
Foreign currency forward contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(51,401)	(19,151)	24,309
Foreign currency forward contracts \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	21,689	(1,521)	(4,450)
Foreign currency forward contracts \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Accumulated other comprehensive income (loss)	6,466	(4,535)	11,685
Credit default swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(9,084)	3,479	(1,304)
Total return swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(6)	1,314	(5,479)
Equity futures \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	(69,972)	0	(30,045)
Warrants \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized on derivatives	$ 632	$ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669646-108580

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