ACCOUNTS RECEIVABLE (Details) (USD $)	12 Months Ended
Jan. 02, 2015	Dec. 27, 2013	Dec. 28, 2012
Accounts receivable
Gross	$ 26,021,000	$ 23,187,000
Allowance for doubtful accounts	(662,000)	(385,000)	(303,000)
Net	25,359,000	22,802,000
Movements in the allowance for doubtful accounts
Balance as of the beginning of the year	385,000	303,000	421,000
Provision for doubtful accounts	486,000us-gaap_ProvisionForDoubtfulAccounts	189,000us-gaap_ProvisionForDoubtfulAccounts	220,000us-gaap_ProvisionForDoubtfulAccounts
Write-offs of uncollectible accounts	(209,000)	(107,000)	(341,000)
Recoveries of accounts written off			3,000
Balance as of the end of the year	662,000	385,000	303,000
Accounts Receivable. \| Credit concentration risk
Movements in the allowance for doubtful accounts
Number of clients representing concentration risk on outstanding receivables	1
Percentage of outstanding receivables accounted for by one client	17.00%	26.00%
Billed
Accounts receivable
Gross	13,151,000	12,879,000
Unbilled
Accounts receivable
Gross	12,170,000	9,635,000
Contract retentions
Accounts receivable
Gross	$ 700,000	$ 673,000

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Amount of recoveries of receivables doubtful of collection that were previously charged off.

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No definition available.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Amounts due from customers or clients , within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services that have been delivered or sold in the normal course of business and amounts included in cost of uncompleted contracts in excess of related billings, or unbilled accounts receivable, which is expected to be collected within one year (or one operating cycle, if longer) from the date of the balance sheet.

+ References

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For an entity that discloses a concentration risk in relation to quantitative amount, the number of clients representing the concentration risk.

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