STOCK-BASED COMPENSATION - Valuation Assumptions (Details) - $ / shares	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018
Performance Shares Stock Options Other Forms Of Compensation And Common Share Repurchases [Abstract]
Weighted-average fair value of options granted during the period	$ 2.33	$ 3.39
Expected life (in years)	5 years 6 months	6 years 1 month 6 days
Expected dividend	0.00%	0.00%
Expected stock volatility	50.31%	46.66%
Risk-free interest rate	2.50%	2.70%

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No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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