Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 62,738	$ 98,414	$ 87,162
Available-for-sale marketable securities
Unrealized holding gains (losses) arising during period (Net of deferred taxes of $62, $19 and $239, respectively)	(177)	(43)	348
Accumulated change in effective tax rate		1,042
Reclassification adjustment for (gains) losses included in net income (Net of deferred taxes of $14, $11 and $180, respectively)	40	29	(257)
Other comprehensive income (loss), net of tax	(137)	1,028	91
Comprehensive income, net of tax	$ 62,601	$ 99,442	$ 87,253

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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