Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock option plan (Narrative) (Details) - USD ($)					3 Months Ended		9 Months Ended
Stock option plan (Narrative) (Details) - USD ($)	May 04, 2019	May 03, 2018	Nov. 10, 2016	Sep. 04, 2014	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018	Oct. 31, 2018
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares authorized							300,000
Shares available for issuance					442,060		442,060
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan term	10 years	10 years	10 years	10 years
Vesting term	5 years	5 years	5 years	5 years			5 years
Options granted during period	5,000	38,000	38,000	246,000			5,000
Options granted during period, price per share	$ 15.00	$ 15.50	$ 21.00	$ 18.45			$ 15.00
Compensation expense related to stock options					$ 35,000	$ 34,000	$ 104,000	$ 95,000
Unrecognized compensation cost					$ 137,000		$ 137,000		$ 305,780
Unrecognized compensation cost, recognition period					2 years 1 month 6 days		2 years 1 month 6 days
Aggregate intrinsic value of options expected to vest					$ 73,000		$ 73,000
Aggregate intrinsic value of options exercisable					$ 13,000		$ 13,000