Balance Sheet Details - Schedule of Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 27, 2021	Dec. 26, 2020
Other Liabilities Current [Abstract]
Customer deposits	$ 17,106	$ 15,177
Current operating lease obligations	$ 5,605	$ 4,470
Operating Lease Liability Current Statement Of Financial Position [Extensible List]	onto:OperatingLeaseLiabilityCurrentMember	onto:OperatingLeaseLiabilityCurrentMember
Income tax payable	$ 2,543	$ 4,109
Accrued professional fees	1,261	1,184
Other	3,926	3,559
Total other current liabilities	$ 30,441	$ 28,499

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Indicates line item in statement of financial position that includes current operating lease liability.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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