EQUITY - Long term incentive plans (Details) - Common stock equivalents - USD ($) $ in Millions		6 Months Ended
Jul. 02, 2018	Dec. 31, 2018
Individual Non-employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	6,677
Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted	40,062
Vesting period	2 years
Total expense recognized		$ 0.3

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
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-Section 50
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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