Investments, at Fair Value - Debt Securities, Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2022	Mar. 31, 2023	Dec. 31, 2021	Dec. 31, 2020
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Beginning balance	$ 31,290	$ 18,669	$ 13,726	$ 18,669	$ 0	$ 0
Increase in OTTI amounts previously recognized	0	12,608	4,943	12,621	0	0
Ending balance	$ 31,290	$ 31,277	18,669	31,290	13,726	0
Credit related OTTI not previously recognized			$ 0	$ 0	$ 13,726	$ 0

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-8B

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-8B

+ Details

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- Definition

Amount of increase (decrease) in the cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-8B

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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