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Marketable Securities - Schedule of Marketable Securities by Category (Details) - USD ($) $ in Thousands | Mar. 28, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 190,887 | $ 189,309
Gross Unrealized Holding Gains | 318 | 260
Gross Unrealized Holding Losses | 576 | 6
Fair Value | 190,629 | 189,563
Municipal notes and bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 70,499 | 80,926
Gross Unrealized Holding Gains | 296 | 188
Gross Unrealized Holding Losses | 10 | 6
Fair Value | 70,785 | 81,108
Asset-backed securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 12,216 | 10,767
Gross Unrealized Holding Gains | 2 | 12
Gross Unrealized Holding Losses | 59 |
Fair Value | 12,159 | 10,779
Certificates of deposits [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 33,154 | 30,500
Gross Unrealized Holding Gains | 13 | 7
Gross Unrealized Holding Losses | 262 |
Fair Value | 32,905 | 30,507
Commercial paper [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 42,511 | 30,707
Gross Unrealized Holding Gains | 1 | 1
Gross Unrealized Holding Losses | 66 |
Fair Value | 42,446 | 30,708
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 32,507 | 36,409
Gross Unrealized Holding Gains | 6 | 52
Gross Unrealized Holding Losses | 179 |
Fair Value | $ 32,334 | $ 36,461

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