Earnings per Common Share - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Sep. 28, 2018	Sep. 29, 2017
Computation Of Earnings Per Share [Line Items]
Repurchase of common stock	$ 3,765	$ 370
Common Stock Repurchase Plan
Computation Of Earnings Per Share [Line Items]
Shares repurchased	57
Shares repurchased, average cost per share	$ 66.16

Computation of earnings per share.

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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Total cost of shares repurchased divided by the total number of shares repurchased.

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