Reserve for Estimated Costs (Detail) - USD ($) $ in Thousands	Apr. 30, 2016	Jul. 31, 2015
Accrued Expenses [Line Items]
Reserve for estimated costs during the Dissolution period	$ 1,700
Liquidation Basis of Accounting
Accrued Expenses [Line Items]
Reserve for estimated costs during the Dissolution period	1,705	$ 1,776
Liquidation Basis of Accounting | Compensation and consulting costs
Accrued Expenses [Line Items]
Reserve for estimated costs during the Dissolution period	602	376
Liquidation Basis of Accounting | Professional fees
Accrued Expenses [Line Items]
Reserve for estimated costs during the Dissolution period	358	568
Liquidation Basis of Accounting | Other expenses associated with wind-down activities
Accrued Expenses [Line Items]
Reserve for estimated costs during the Dissolution period	528	646
Liquidation Basis of Accounting | Insurance
Accrued Expenses [Line Items]
Reserve for estimated costs during the Dissolution period	$ 217	$ 186