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Capital Stock - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Apr. 01, 2018	May 08, 2018
Equity Class Of Treasury Stock [Line Items]
Stock repurchase program, authorized amount			$ 65,000,000
Common stock repurchased value	$ 1,144,000	$ 63,000
Stock Repurchase Program [Member]
Equity Class Of Treasury Stock [Line Items]
Common stock shares repurchased	135,000
Common stock repurchased value	$ 1,100,000

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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