Deferred Stock Activity (Detail) - Deferred Stock $ / shares in Units, shares in Thousands, $ in Thousands	4 Months Ended
Apr. 18, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Balance at beginning of period \| shares	49
Shares, Vested \| shares	(2)
Shares, Granted \| shares	2
Shares, Balance at end of period \| shares	49
Weighted Average Fair Value, Balance at beginning of period \| $ / shares	$ 22.31
Weighted Average Fair Value, Vested \| $ / shares	18.47
Weighted Average Fair Value, Granted \| $ / shares	21.74
Weighted Average Fair Value, Balance at end of period \| $ / shares	$ 22.49
Weighted Average Remaining Contractual Term (Years)	3 months
Unrecognized compensation cost \| $	$ 149

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, 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 equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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