Disaggregation of Sales, Geographic Sales and Product Sales - Net Sales by Geographic Areas (Details) - USD ($) $ in Thousands		3 Months Ended
		Apr. 02, 2021	Apr. 03, 2020
Geographic And Sales [Line Items]
Total net sales		$ 50,752	$ 35,187
Geographic Distribution, Domestic [Member]
Geographic And Sales [Line Items]
Total net sales		2,340	1,739
Geographic Distribution, Foreign [Member]
Geographic And Sales [Line Items]
Total net sales		48,412	33,448
Geographic Distribution, Foreign [Member] | China [Member]
Geographic And Sales [Line Items]
Total net sales		19,643	11,715
Geographic Distribution, Foreign [Member] | JAPAN
Geographic And Sales [Line Items]
Total net sales		9,603	8,302
Geographic Distribution, Foreign [Member] | Other [Member]
Geographic And Sales [Line Items]
Total net sales	[1]	$ 19,166	$ 13,431

[1] No other location individually exceeds 10% of the total sales.