Detail of Certain Balance Sheet Accounts - Schedule of Trade Receivables (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Amounts billed	$ 5,523	$ 8,029
Amounts unbilled	5,576	2,368
Retainage	572	16
Less: Allowance for uncollectible accounts	(236)	(202)
Trade receivables, net	$ 11,435	$ 10,211

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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The amount of assets, typically cash, provided to suppliers of goods in advance of receipt and acceptance, or services (such as research facilities, lawyers or consultants), which is held by such parties until the entity either effects full payment (including applying the retainer) or obtains release from liability.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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