Balance Sheet Components - Prepaid Expenses And Other Current Assets (Details) - USD ($) $ in Thousands		Mar. 27, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
French R&D tax credits receivable(1)	[1]	$ 7,163	$ 7,343
Contract assets(2)		5,806	13,969
Deferred cost of revenue		3,892	2,631
Prepaid maintenance, royalty, rent, and property taxes		3,653	1,594
Capitalized sales commissions		1,168	1,309
Other		10,319	13,916
Prepaid Expense and Other Assets, Current		$ 32,001	$ 40,762

[1] The Company’s French subsidiary participates in the French Crédit d’Impôt Recherche program (the “R&D tax credits”) which allows companies to monetize eligible research expenses. The R&D tax credits can be used to offset against income tax payable to the French government in each of the four years after being incurred, or if not utilized, are recoverable in cash. The amount of R&D tax credits recoverable are subject to audit by the French government. The R&D tax credits receivable at March 27, 2020 were approximately $23.5 million and are expected to be recoverable from 2020 through 2023.