Continuing operations and reported as discontinued operations (Details) - Comnet Telecom Division [Member] - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 30, 2018	Apr. 30, 2018
Major line items constituting pretax income from discontinued operations:
Net sales	$ 1,866	$ 4,240
Cost of sales	(1,429)	(3,194)
Gross profit	437	1,046
Selling, general and administrative expense	(380)	(793)
Pretax income from discontinued operations	57	253
Provision for income taxes	18	64
Income from discontinued operations	$ 39	$ 189

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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