Balance Sheet Components - Short-Term Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Short-term marketable securities term	2 years
Short-term marketable securities:
Maturing within one year	$ 0	$ 7,454
Maturing between one and two years	0	2,170
Total marketable securities	$ 0	$ 9,624

Term Of Maturities Of Investments Considered Short-Term

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