Fair Value Measurements - Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023
Financial assets:
Fair value investments	$ 20,154	$ 21,586
Total financial assets	95,430	66,338
Financial liabilities:
Secured financing	14,149	14,228
Total financial liabilities	14,149	14,228
Consolidated VIEs
Financial assets:
Fair value investments	75,276	44,752
Level 1
Financial assets:
Fair value investments	6,005	7,358
Total financial assets	6,005	7,358
Financial liabilities:
Secured financing	0	0
Total financial liabilities	0	0
Level 1 | Consolidated VIEs
Financial assets:
Fair value investments	0	0
Level 2
Financial assets:
Fair value investments	0	0
Total financial assets	0	0
Financial liabilities:
Secured financing	0	0
Total financial liabilities	0	0
Level 2 | Consolidated VIEs
Financial assets:
Fair value investments	0	0
Level 3
Financial assets:
Fair value investments	14,149	14,228
Total financial assets	68,774	35,391
Financial liabilities:
Secured financing	14,149	14,228
Total financial liabilities	14,149	14,228
Level 3 | Consolidated VIEs
Financial assets:
Fair value investments	54,625	21,163
NAV
Financial assets:
Fair value investments	0	0
Total financial assets	20,651	23,589
Financial liabilities:
Secured financing	0	0
Total financial liabilities	0	0
NAV | Consolidated VIEs
Financial assets:
Fair value investments	$ 20,651	$ 23,589