Earnings Per Share - Computation of Basic and Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018
Earnings Per Share Basic [Line Items]
Net income (loss)	$ 1,664	$ (1,309)
Weighted-average shares of common stock outstanding:
Basic	21,029	20,942
Dilutive effect of common stock equivalents arising from share option, nonvested share and nonvested share unit awards	25
Diluted	21,054	20,942
Basic earnings (loss) per share	$ 0.08	$ (0.06)
Diluted earnings (loss) per share	$ 0.08	$ (0.06)
Share Option Awards [Member]
Weighted-average shares of common stock outstanding:
Antidilutive shares/unit awards excluded from diluted calculation	422	183
Nonvested Share Awards and Nonvested Share Unit Awards [Member]
Weighted-average shares of common stock outstanding:
Antidilutive shares/unit awards excluded from diluted calculation	406	387

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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