REVENUE RECOGNITION - Impact of Topic 606 on Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 27, 2019	Sep. 30, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unbilled contract revenue	$ 10,003	$ 9,529
Inventories	44,959	44,267
Deferred income taxes	6,834	7,154
Accumulated deficit	$ (14,086)	$ (15,275)

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as noncurrent.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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