Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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GOODWILL (Details Textual) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
GOODWILL (Details Textual) $ in Thousands	Sep. 26, 2020 USD ($) Reporting_Unit	Mar. 28, 2020 USD ($) Reporting_Unit	Sep. 28, 2019 USD ($)	Sep. 26, 2020 USD ($)	Sep. 28, 2019 USD ($)	Dec. 28, 2019 USD ($)	Dec. 29, 2018 USD ($)
Goodwill [Line Items]
Impairment of goodwill	$ 0	$ 2,969	$ 0	$ 2,969	$ 0	$ 0
Number of reporting units \| Reporting_Unit	1	1
Goodwill	$ 26,277			$ 26,277		$ 31,049	$ 32,061
Reporting Unit X [Member]
Goodwill [Line Items]
Percent of fair value of reporting unit excess of carrying value	2.40%			2.40%
Goodwill	$ 14,200			$ 14,200