Discontinued operations - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2015	Oct. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Royalty revenue	$ 93	$ 161
Radio Mobile, Inc
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Royalty revenue	69
RF Neulink
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Royalty revenue	$ 24