Stock-Based Compensation - Stock-based compensation costs (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Stock-Based Compensation
Stock-based compensation cost	$ 60,091	$ 54,799	$ 50,077
Income tax benefit	3,616	2,476	8,890
Share based compensation costs after tax	56,475	52,323	41,187
Total unrecognized compensation costs related to awards	$ 78,600
Weighted-average period of recognition of unrecognized compensation costs	2 years 2 months 12 days
Reserved shares of common stock for future issuance	1,823
Cost of revenues
Stock-Based Compensation
Stock-based compensation cost	$ 1,477	1,316	1,238
Research and development
Stock-Based Compensation
Stock-based compensation cost	29,212	26,187	23,867
Selling, general and administrative
Stock-Based Compensation
Stock-based compensation cost	$ 29,402	$ 27,296	$ 24,972
2009 Stock Incentive Plan
Stock-Based Compensation
Reserved shares of common stock for future issuance	1,223
2009 Employee Stock Purchase Plan
Stock-Based Compensation
Reserved shares of common stock for future issuance	600

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

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