Investments, at Fair Value - Continuous Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Mar. 31, 2023
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Total available-for-sale debt securities with unrealized losses	$ 2,129	$ 75,900
Unrealized Losses, Total available-for-sale debt securities with unrealized losses	1,060	8,880
Corporate debt securities (L Bonds)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Twelve months or longer	0	73,822
Unrealized Losses, Twelve months or longer	0	7,924
Other debt securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value, Less than twelve months	0	2,078
Fair Value, Twelve months or longer	2,129	0
Unrealized Losses, Less than twelve months	0	956
Unrealized Losses, Twelve months or longer	$ 1,060	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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