Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Mar. 27, 2020
Share-based compensation arrangement by share-based payment award [Line Items]
Unrecognized compensation expense related to stock compensation plans	$ 370
Share-based payment arrangement, nonvested award, cost not yet recognized, period for recognition	4 years 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 431
Restricted stock [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Unrecognized compensation expense related to stock compensation plans	$ 574
Share-based payment arrangement, nonvested award, cost not yet recognized, period for recognition	4 years 3 months 18 days
Stock option expense recognised	$ 95
Employee Stock Option [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Stock option expense recognised	$ 61
Twenty twenty equity incentive plan [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Stock based compensation number of shares authorized		238,467
Twenty twenty equity incentive plan [Member] \| Restricted stock [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Stock based compensation number of shares authorized		95,387

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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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