Detail of Certain Balance Sheet Accounts (Details) - USD ($) $ in Thousands	Dec. 26, 2020	Dec. 28, 2019
Balance Sheet Related Disclosures [Abstract]
Amounts billed	$ 5,050	$ 5,523
Amounts unbilled	1,455	5,576
Retainage	1,670	572
Less: allowance for uncollectible accounts	(386)	(236)
Trade receivables, net	$ 7,789	$ 11,435

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
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- References

No definition available.

+ Details

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- Definition

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.

+ References

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- Definition

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.

+ References

No definition available.

+ Details

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