DERIVATIVE FINANCIAL INSTRUMENTS - Fair Values (Details) - Designated as hedging instruments - Interest swap agreement - USD ($) $ in Thousands	Jul. 03, 2020	Dec. 27, 2019
Accrued liabilities.
Derivatives, Fair Value [Line Items]
Fair value of Derivative Instruments	$ (658)	$ (241)
Other noncurrent (liabilities) assets
Derivatives, Fair Value [Line Items]
Fair value of Derivative Instruments	$ (351)	$ (306)

Fair value of the assets less the liabilities of a derivative or group of derivatives.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

Name:	us-gaap_DerivativeFairValueOfDerivativeNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant