FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Liabilities:
Convertible Notes, Carrying Value	$ 106,104	$ 101,587
Fair Value, Measurements, Recurring [Member]
Financial Assets:
Deferred compensation assets	1,838	2,035
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Deferred compensation assets	460	493
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Deferred compensation assets	1,378	1,542
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Deferred compensation assets	0	$ 0
Convertible Debt [Member]
Liabilities:
Convertible Notes, Fair Value Disclosure	$ 95,100

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Fair value portion of notes payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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