Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 12,843	$ 5,590
Other comprehensive income, before tax:
Unrealized gains on derivative instruments	23	692
Unrealized gains (losses) on available-for-sale securities	15	(38)
Other comprehensive income, before tax	38	654
Tax provision related to derivative instruments	(6)	(61)
Tax provision related to available-for-sale securities	(3)	(11)
Other comprehensive income, net of tax	29	582
Comprehensive income	$ 12,872	$ 6,172

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

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