OTHER FINANCIAL STATEMENT INFORMATION - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Oct. 01, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 160,983	$ 153,712
Less: accumulated depreciation and amortization	(117,135)	(110,571)
Total	43,848	43,141
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	76,357	72,731
Capitalized software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	38,107	37,141
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	40,489	38,718
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,880	2,913
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,150	$ 2,209

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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