Fair Value of Financial Instruments - Changes in Fair Value of Investments Using Level 3 Inputs (Details) $ in Thousands	9 Months Ended
	Dec. 31, 2022 USD ($)
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Purchases or originations	$ 808,259
Net change in unrealized gains (losses)	$ (228)
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Unrealized Gain Loss On Investments
Net amortization of discount on investment	$ 770
Balance, End of Period	808,801
First-lien Debt Investments
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Purchases or originations	800,453
Net change in unrealized gains (losses)	(228)
Net amortization of discount on investment	770
Balance, End of Period	800,995
Equity and Other Investments
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Purchases or originations	7,806
Balance, End of Period	$ 7,806