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Segments and Geographic Information - Revenue by Market (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Revenue from External Customers [Line Items]
Revenues	$ 693,616	$ 589,464	$ 529,675
Foundry & Logic
Revenue from External Customers [Line Items]
Revenues	446,183	318,552	258,459
DRAM
Revenue from External Customers [Line Items]
Revenues	109,734	147,257	135,333
Flash
Revenue from External Customers [Line Items]
Revenues	25,822	25,554	40,477
Systems
Revenue from External Customers [Line Items]
Revenues	$ 111,877	$ 98,101	$ 95,406

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