Liquidation Basis of Accounting - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
	Apr. 29, 2016	Apr. 30, 2016	Apr. 30, 2016	Apr. 25, 2015	Feb. 12, 2016	Jul. 31, 2015	Jan. 24, 2015	Jul. 31, 2014
Statutory Accounting Practices [Line Items]
Liquidating distribution	$ 8,376
Cash and cash equivalents		$ 3,990	$ 3,990
Other assets		50	50
Reserve for estimated costs during the Dissolution period		1,700	1,700
Other liabilities		1,590	1,590
Decrease in net assets			(950)
(Increase) decrease in estimated costs during the dissolution period		1,440	1,440
Reserve for Previously Estimated Costs
Statutory Accounting Practices [Line Items]
(Increase) decrease in estimated costs during the dissolution period			440
Accrued Expenses
Statutory Accounting Practices [Line Items]
(Increase) decrease in estimated costs during the dissolution period			50
Other expenses associated with wind-down activities
Statutory Accounting Practices [Line Items]
(Increase) decrease in estimated costs during the dissolution period		410	410
Other expenses associated with wind-down activities | Reserve for Previously Estimated Costs
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		350	350
Compensation and consulting costs
Statutory Accounting Practices [Line Items]
(Increase) decrease in estimated costs during the dissolution period		450	450
Compensation and consulting costs | Reserve for Previously Estimated Costs
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		50	50
Professional fees
Statutory Accounting Practices [Line Items]
(Increase) decrease in estimated costs during the dissolution period		360	360
Professional fees | Reserve for Previously Estimated Costs
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		40	40
Insurance
Statutory Accounting Practices [Line Items]
(Increase) decrease in estimated costs during the dissolution period		220	220
Liquidation Basis of Accounting
Statutory Accounting Practices [Line Items]
Net assets in liquidation		756	756	$ 9,584	$ 9,132	$ 10,080	$ 9,573	$ 9,496
Increase (decrease) of net assets			(9,330)
Liquidating distribution		8,376	8,376
Cash and cash equivalents		3,993	3,993			10,943
Other assets		55	55			47
Reserve for estimated costs during the Dissolution period		1,705	1,705			1,776
Other liabilities		1,587	1,587			1,587
(Increase) decrease in estimated costs during the dissolution period			(999)	$ 6
Liquidation Basis of Accounting | Other expenses associated with wind-down activities
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		528	528			646
Liquidation Basis of Accounting | Compensation and consulting costs
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		602	602			376
Liquidation Basis of Accounting | Professional fees
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		358	358			568
Liquidation Basis of Accounting | Insurance
Statutory Accounting Practices [Line Items]
Reserve for estimated costs during the Dissolution period		217	217			$ 186
IQstream Patents
Statutory Accounting Practices [Line Items]
Net assets in liquidation		$ 0	$ 0