Reserves for Expected Costs of Liquidation and Residual Wind-Down Claims - Summary of Activity in Reserves for Residual Wind-Down Claims (Detail) - Liquidation Basis of Accounting [Member] - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period	$ 25,406	$ 28,698
Less claims allowed during the period	(1,566)	(363)
Balance, end of period	$ 23,840	$ 28,335