CONTINGENT LIABILITIES (Narrative) (Details) $ in Millions	3 Months Ended	12 Months Ended
Mar. 30, 2019 USD ($) Item	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Number of lawsuits against the company \| Item	7
Minimum limit of per claim for providing insurance coverage on annual basis	$ 5.0
Maximum limit of aggregate loss incurred annually for providing insurance coverage on annual basis	$ 10.0
Total amount of damages claimed		$ 0.1	$ 0.1

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
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-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

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