FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (FV) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Interest rate swap agreement \| Other long-term liabilities
Assets and liabilities measured at fair value on a recurring basis
Liabilities	$ 1,800	$ 900
Recurring basis \| Level 1
Assets and liabilities measured at fair value on a recurring basis
Assets	29,143	27,031
Recurring basis \| Level 1 \| Money market funds \| Cash and cash equivalents
Assets and liabilities measured at fair value on a recurring basis
Assets	27,105	24,904
Recurring basis \| Level 1 \| Voluntary Savings Plan - mutual funds held in trust
Assets and liabilities measured at fair value on a recurring basis
Assets	2,038	2,127
Recurring basis \| Level 2 \| Interest rate swap agreement \| Other long-term liabilities
Assets and liabilities measured at fair value on a recurring basis
Liabilities	$ 1,796	$ 897

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value of all liability derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

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- Definition

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.

+ References

No definition available.

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