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Balance Sheet Components (Schedule of Changes in Carrying Value of Long-term Investments) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 29, 2020 | Jun. 28, 2020 | Jun. 30, 2019
Balance Sheet Related Disclosures [Abstract] |  |  |
Carrying value as of the beginning of the period | $ 8,147 | $ 8,147 | $ 2,886
Additions from purchase of investments |  | 5,815 | 5,200
Impairment | $ (4,500) | (4,530) | 0
Carrying value as of the end of the period |  | $ 9,432 | $ 8,086

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