Liquidating Distributions - Schedule of Liquidating Distributions (Detail) - Liquidation Basis of Accounting [Member] - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Distribution Made to Limited Liability Company (LLC) Member [Line Items]
Distributions during the year	$ 67,818	$ 40	$ 433
Less: Liquidating distributions payable as of beginning of year	(1,785)	(1,825)	(9,205)
Add: Liquidating distributions payable as of end of year	351,876	1,785	1,825
Total (net reversal)	$ 417,909	$ 0	$ (6,947)