FAIR VALUE MEASUREMENT - Reconciliation (Details) $ in Thousands	3 Months Ended
Mar. 28, 2020 USD ($)
FAIR VALUE MEASUREMENT
Beginning balance	$ 496
Change due to vesting of awards granted	166
Change in fair value measurement of liability	(52)
Ending balance	610
PE and PEAR awards \| Level 3
FAIR VALUE MEASUREMENT
Beginning balance	496
Change due to vesting of awards granted	166
Change in fair value measurement of liability	(52)
Ending balance	$ 610

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Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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