FAIR VALUE (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Fair Value on a Recurring Basis [Member]
Financial Assets (Liabilities) [Abstract]
Cash equivalents and current investments	$ 40,070	$ 50,307
Other long-term assets	3,472	2,782
Forward contracts	275	1,371
Life insurance contracts	36,747	32,286
Financial assets (liabilities), net	80,564	86,746
Fair Value on a Recurring Basis [Member] \| Level 1 [Member]
Financial Assets (Liabilities) [Abstract]
Cash equivalents and current investments	40,070	50,307
Other long-term assets	3,472	2,782
Forward contracts	0	0
Life insurance contracts	0	0
Financial assets (liabilities), net	43,542	53,089
Fair Value on a Recurring Basis [Member] \| Level 2 [Member]
Financial Assets (Liabilities) [Abstract]
Cash equivalents and current investments	0	0
Other long-term assets	0	0
Forward contracts	275	1,371
Life insurance contracts	0	0
Financial assets (liabilities), net	275	1,371
Fair Value on a Recurring Basis [Member] \| Level 3 [Member]
Financial Assets (Liabilities) [Abstract]
Cash equivalents and current investments	0	0
Other long-term assets	0	0
Forward contracts	0	0
Life insurance contracts	36,747	32,286
Financial assets (liabilities), net	36,747	$ 32,286
Life Insurance Contracts [Member]
Changes in Fair Value of Level 3 Marketable Securities [Roll Forward]
Beginning balance	32,286
Actual Return on Plan Assets [Abstract]
Relating to assets still held at the reporting date	3,835
Purchases and issuances	895
Sales and settlements	(269)
Transfers into Level 3	0
Ending balance	$ 36,747

No definition available.

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- Definition

Fair value portion of cash equivalents with banks or financial institutions and current investments, including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

+ References

No definition available.

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Amount of purchases and issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

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Amount of sale and settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

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- Definition

Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value of asset after deduction of liability.

+ References

No definition available.

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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- Definition

Fair value portion of other assets.

+ References

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