Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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- Definition

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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- Definition

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

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No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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Stock Option Plan and Restricted Stock Plan - Additional Information (Detail) - USD ($)									1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 26, 2019	Apr. 23, 2019	Oct. 23, 2018	Apr. 24, 2018	Oct. 24, 2017	Apr. 25, 2017	Oct. 25, 2016	Oct. 27, 2015	Jun. 26, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting period			3 years
Risk-free interest rate									1.83%
Expected dividend yield									1.62%
Expected life									6 years 7 months 20 days
Expected volatility									26.69%
Weighted-average grant-date fair value of options granted									$ 7.31
Stock compensation expense										$ 313,000	$ 377,000	$ 625,000	$ 754,000
Granted, Shares									398,850					0
Granted the period exercise price									$ 29.70
Restricted Stock [Member] \| Non-Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted		660,000		21,420		29,300
Restricted shares value		$ 21,714		$ 540,000		$ 600,000
Restricted Stock [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense										135,000	140,000	270,000	290,000
Restricted Stock [Member] \| Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares vesting period	3 years						3 years	3 years
Restricted shares granted	25,818		52,042		28,382		30,810	62,546
Restricted shares value	$ 766,000		$ 1,440,000		$ 655,000		$ 560,000	$ 1,060,000
Stock compensation expense										$ 210,000	$ 158,000	$ 415,000	$ 326,000