Stock-Based Compensation - Stock-based compensation costs (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Stock-Based Compensation
Stock-based compensation cost	$ 54,799	$ 50,077	$ 44,752
Income tax benefit	2,476	8,890	11,073
Share based compensation costs after tax	52,323	41,187	33,679
Total unrecognized compensation costs related to awards	$ 59,600
Weighted-average period of recognition of unrecognized compensation costs	2 years
Reserved shares of common stock for future issuance	2,592
Cost of revenues
Stock-Based Compensation
Stock-based compensation cost	$ 1,316	1,238	1,090
Research and development
Stock-Based Compensation
Stock-based compensation cost	26,187	23,867	21,771
Selling, general and administrative
Stock-Based Compensation
Stock-based compensation cost	$ 27,296	$ 24,972	$ 21,891
2009 Stock Incentive Plan
Stock-Based Compensation
Reserved shares of common stock for future issuance	1,815
2009 Employee Stock Purchase Plan
Stock-Based Compensation
Reserved shares of common stock for future issuance	777

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

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