Reserves for Expected Costs of Liquidation and Residual Wind-Down Claims and Costs - Summary of Activity in Reserves for Residual Wind-Down Claims and Costs (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period			$ 177
Plus addition to reserves
Balance, end of period	178		178
Liquidation Basis of Accounting [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period	178	$ 169	177	$ 169
Plus addition to reserves			1
Balance, end of period	$ 178	$ 169	$ 178	$ 169