Investments at Fair Value - Summary of Investments at Fair Value (Details) $ in Thousands	9 Months Ended
Dec. 31, 2022 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 809,029
Fair Value	808,801
Net Unrealized Gain (Loss)	(228)
First-lien Debt Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	801,223
Fair Value	800,995
Net Unrealized Gain (Loss)	(228)
Equity and Other Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	7,806
Fair Value	$ 7,806

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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