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Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020	Dec. 31, 2020
Government Grants [Line Items]
Provision for income taxes	$ (165,000)	$ 642,000	$ (132,000)	$ 909,000
Income tax provision on earnings of subsidiaries	189,000	369,000	208,000	548,000
Deferred payroll tax liability					$ 764,000
Proceeds From Government Grants		310,000	66,000	310,000
Grant [Member] \| Cost of Sales [Member]
Government Grants [Line Items]
Proceeds From Government Grants		180,000	39,000	180,000
Grant [Member] \| Research and Development Expense [Member]
Government Grants [Line Items]
Proceeds From Government Grants		49,000	10,000	49,000
Grant [Member] \| Selling, General and Administrative Expenses [Member]
Government Grants [Line Items]
Proceeds From Government Grants		81,000	17,000	81,000
Foreign Tax Authority \| Singapore
Government Grants [Line Items]
Income tax charge (benefit)	$ 24,000	$ 272,000	$ 72,000	$ 373,000