Percentage of conversion price equaling stock price.

No definition available.

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- Definition

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.

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

+ References

No definition available.

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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Stock-Based Compensation (Deferred Stock) - Additional Information (Detail) - shares	4 Months Ended	6 Months Ended	12 Months Ended
	Apr. 18, 2020	Jul. 11, 2020	Dec. 27, 2020	Dec. 28, 2019	Dec. 29, 2018
Deferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares vested	2,707	49,000
Common shares issued	2,707
Annual Grants \| Deferred Stock \| Non Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate shares elected to receive		15,979		46,240
Common shares issued				17,340
Annual Grants \| Deferred Stock \| Non Employee Directors \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					1 year
Annual Grants \| Deferred Stock \| Non Employee Directors \| Scenario Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate shares elected to receive			39,900
Retainer Conversion
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Retainers conversion into deferred shares		100.00%
Vesting period		1 year
Previous Director Retainer Deferrals \| Deferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares vested		4,660
Common shares issued		4,660
Director Retainer Deferrals \| Omnibus Plan \| Deferred Stock \| Non Employee Directors \| Scenario Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate shares elected to receive			2,299