Marketable Securities - Summary of Estimated Fair Value and Gross Unrealized Holding Losses of Marketable Securities in Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
In Unrealized Loss Position For Less Than 12 Months, Fair Value	$ 28,381	$ 14,166
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses	34	6
In Unrealized Loss Position For Greater Than 12 Months, Fair Value	0	0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses	0	0
Municipal notes and bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
In Unrealized Loss Position For Less Than 12 Months, Fair Value	6,026	14,166
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses	6	6
In Unrealized Loss Position For Greater Than 12 Months, Fair Value	0	0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses	0	$ 0
Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
In Unrealized Loss Position For Less Than 12 Months, Fair Value	4,497
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses	1
In Unrealized Loss Position For Greater Than 12 Months, Fair Value	0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses	0
Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
In Unrealized Loss Position For Less Than 12 Months, Fair Value	17,858
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses	27
In Unrealized Loss Position For Greater Than 12 Months, Fair Value	0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses	$ 0