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) - Liquidation Basis of Accounting [Member] - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period	$ 966	$ 19,957
Plus addition to reserves	9
Less claims allowed during the period	(815)	(2,437)
Less costs incurred by trust professionals		(1)
Balance, end of period	$ 160	$ 17,519