Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Period Type:	duration

Stockholders' Equity - Share repurchase programs (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 31, 2016	Oct. 31, 2018	Jul. 01, 2017
Share Repurchase Programs
Value of shares repurchased and retired	$ 39,276	$ 40,543
Common Stock
Common Stock
Number of shares issued during the period	800
Share Repurchase Programs
Number of shares repurchased and retired	434	893
Value of shares repurchased and retired	$ 39,300	$ 40,500
Program Authorization Date October 2017
Share Repurchase Programs
Program amount authorized to repurchase	200,000		$ 200,000	$ 100,000
Program Authorization Date January 2017
Share Repurchase Programs
Program amount authorized to repurchase	100,000
Program Authorization Date August 2015
Share Repurchase Programs
Program amount authorized to repurchase	$ 100,000