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Cash, Cash Equivalents, and Investments Cash, Cash Equivalents, and Investments - Schedule of Allowance for Credit Loss Activity (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 27, 2020
Sep. 29, 2019
Sep. 27, 2020
Sep. 29, 2019
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]        
Balance as of December 31, 2019     $ 0  
Increases to the allowance for credit losses $ 0 $ 0 160,000 $ 0
Decreases to the allowance for credit losses 0 $ 0 (85,000) $ 0
Write-offs     0  
Balance as of September 27, 2020 $ 75,000   $ 75,000