ACCOUNTING POLICIES ACCOUNTING POLICIES (Details 6) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASU No. 2016-09
Derivative Instruments, Gain (Loss) [Line Items]
Cumulative effect of new accounting pronouncement in period of adoption	$ 9,000
Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recorded during period	581	$ (1,389)
Interest rate swap \| Designated as hedging instrument \| Current and Other long-term liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Outstanding notional	45,760	20,466
Fair value	(1,816)	(2,397)
Interest Rate Derivatives, Increase (Decrease) in Fair Value Adjustments	(1,816)	(2,397)	$ (1,008)
Interest rate swap \| Designated as hedging instrument \| Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in OCI on derivative (effective portion) net of tax	(110)	(809)
Amount of gain (loss) reclassified from Accumulated OCI into income (effective portion)	5	0
Amount of gain (loss) recognized in income on derivative (ineffective portion)	$ 0	$ (124)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Interest Rate Derivatives, Increase (Decrease) in Fair Value Adjustments

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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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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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as 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 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-Paragraph 4C
-Subparagraph (d)
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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

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-Name Accounting Standards Codification
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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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