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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 31, 2020	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019	Dec. 29, 2020	Dec. 31, 2020	Mar. 27, 2020
Government Grants [Line Items]
Provision for income taxes		$ 642	$ 417	$ 909	$ 971
Income tax provision on earnings of subsidiaries		369	201	548	563
Deferred payroll tax liability		252		252			$ 719	$ 719
Proceeds From Government Grants		310
Subsequent Event [Member]
Government Grants [Line Items]
Proceeds from Income Tax Refunds	$ 157
Grant [Member] \| Cost of Sales [Member]
Government Grants [Line Items]
Proceeds From Government Grants		180
Grant [Member] \| Research and Development Expense [Member]
Government Grants [Line Items]
Proceeds From Government Grants		49
Grant [Member] \| Selling, General and Administrative Expenses [Member]
Government Grants [Line Items]
Proceeds From Government Grants		81
Forecast [Member]
Government Grants [Line Items]
Proceeds From Government Grants						$ 535
Foreign Tax Authority \| Singapore
Government Grants [Line Items]
Income tax charge (benefit)		$ 272	$ 213	$ 373	$ 404