Reconciliation of Average Number of Common Shares and Common Share Equivalents Outstanding (Detail) - shares	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Average number of common shares outstanding	40,161,000	42,038,000
Incremental shares from assumed exercises of stock options	5,000	60,000
Average number of common shares and common share equivalents outstanding	40,166,000	42,098,000