Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Stock-based compensation costs
Stock based compensation costs	$ 13,669	$ 12,119	$ 26,253	$ 24,311
Income tax (expense) benefit	(2,186)	1,677	1,134	6,896
Share based compensation costs after tax	15,855	10,442	25,119	17,415
Total unrecognized compensation costs related to awards	89,100		$ 89,100
Weighted-average period of recognition of unrecognized compensation costs			2 years 2 months 12 days
Cost of revenues
Stock-based compensation costs
Stock based compensation costs	326	294	$ 645	590
Research and development
Stock-based compensation costs
Stock based compensation costs	6,459	5,669	12,556	11,438
Selling, general and administrative
Stock-based compensation costs
Stock based compensation costs	$ 6,884	$ 6,156	$ 13,052	$ 12,283

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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