Amount payable annually for services rendered.

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It represents the total annual compensation granted to non employee director.

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Share based goods and nonemployee services transaction value of stock option issued.

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It represent the term of options vesting period.

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No definition available.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. 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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No definition available.

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The number of shares or units of entity securities issued in the transaction in which equity securities were issued to pay for goods or nonemployee services.

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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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Number of options vested.

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No definition available.

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Stock-based compensation and equity transactions - Additional Information (Detail) - USD ($)				3 Months Ended			6 Months Ended
	Mar. 08, 2019	Dec. 03, 2018	Dec. 13, 2017	Apr. 30, 2019	Jan. 31, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018	Dec. 13, 2018	Nov. 01, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining life of options outstanding							4 years 2 months 23 days
Weighted average remaining contractual life of options exercisable							2 years 11 months 8 days
Weighted average life of options vested and expected to vest							4 years 2 months 19 days
Aggregate intrinsic value of options outstanding				$ 4,108,000			$ 4,108,000
Aggregate intrinsic value of options exercisable				3,119,000			3,119,000
Aggregate intrinsic value of options vested and expected to vest				4,093,000			4,093,000
Non-vested stock-based arrangements yet to be recognized				550,000			$ 550,000
Stock based arrangements yet to be recognized, weighted average period expected to be recognized							5 years 5 months 4 days
Non-employee director annual grant				$ 50,000			$ 50,000
Share-based Compensation							$ 192,000	$ 132,000
Nonqualified Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock option per share					$ 3.471
Share-based Goods and Nonemployee Services Transaction, Quantity of Securities Issued					7,203
Share Based Goods And Non Employee Services Transaction Value Of Stock Option Issued					$ 25,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period					5 years
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price					$ 8.07
Board of Directors Chairman [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount Payable Annually for Services Rendered										$ 15,000
Incentive stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares	5,000		8,000
Share-based compensation arrangement by share-based payment award, options, grants in period, gross	25,000		80,000
Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Period	5 years		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	5,000		8,000						8,000
Incentive stock options \| One Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares		2,000
Share-based compensation arrangement by share-based payment award, options, grants in period, gross		10,000
Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Period		5 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number		2,000
Incentive stock options \| Two Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares		5,000
Share-based compensation arrangement by share-based payment award, options, grants in period, gross		25,000
Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Period		5 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number		5,000
Employee And Non-Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock option per share				$ 8.17		$ 2.44	$ 8.17	$ 2.44
Selling, General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation				$ 78,000		$ 57,000	$ 192,000	$ 132,000