Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 14,304	$ 16,191
Available-for-sale marketable securities
Unrealized holding gains (losses) arising during period (Net of deferred taxes of $243 and ($158), respectively for the thirteen Weeks Ended)	621	(403)
Reclassification adjustment for losses included in net income (Net of deferred taxes of $0 and $15, respectively for the thirteen Weeks Ended)		39
Other comprehensive income gain (loss), net of tax	621	(364)
Comprehensive income, net of tax	$ 14,925	$ 15,827

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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