Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Numerator:
Net income as reported	$ 36,989	$ 36,029
Weighted average shares outstanding
Basic (in shares)	24,717	24,339
Effect of dilutive securities (in shares)	292	436
Diluted (in shares)	25,009	24,775
Earnings Per Share:
Basic earnings per share (in dollars per share)	$ 1.50	$ 1.48
Diluted earnings per share (in dollars per share)	$ 1.48	$ 1.45