Sale of Aviel Electronics division - Additional Information (Detail) - Aviel Electronics Division [Member] - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended
	Dec. 22, 2015	Apr. 30, 2015	Apr. 30, 2016	Apr. 30, 2015
Gain (Loss) on Disposition of Assets, Total	$ 35,000
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	$ 150,000
Discontinued Operation, Intra-Entity Amounts, Discontinued Operation after Disposal, Revenue		$ 293,000	$ 86,000	$ 545,000
Income (Loss) from Continuing Operations before Interest Expense, Interest Income, Income Taxes, Extraordinary Items, Noncontrolling Interests, Net		$ 80,000	40,000	$ 106,000
Notes Payable, Other Payables [Member]
Debt Instrument, Term	3 years
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Promissory Note [Member] | Other Current Assets [Member]
Disposal Group, Including Discontinued Operation, Accounts Payable			83,000
Promissory Note [Member] | Other Assets [Member]
Disposal Group, Including Discontinued Operation, Accounts Payable			$ 139,000
Promissory Note [Member] | Notes Payable, Other Payables [Member]
Disposal Group, Including Discontinued Operation, Accounts Payable	$ 250,000