CASH, CASH EQUIVALENTS AND SHORT TERM INVESTMENTS (Components of Cash, Cash Equivalents and Short Term Investments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Cash, Cash Equivalents and Short Term Investments [Line Items]
Cost of cash, cash equivalents and short term investments	$ 29,241	$ 26,311
Gross unrealized gains on cash, cash equivalents and short term investments	56	55
Gross unrealized losses on cash, cash equivalents and short term investments	(50)	(43)
Estimated fair value of cash, cash equivalents and short term investments	29,247	26,323
Government and agency securities [Member]
Cash, Cash Equivalents and Short Term Investments [Line Items]
Cost of cash, cash equivalents and short term investments	9,912	9,857
Gross unrealized gains on cash, cash equivalents and short term investments	31	20
Gross unrealized losses on cash, cash equivalents and short term investments	(8)	(10)
Estimated fair value of cash, cash equivalents and short term investments	9,935	9,867
Corporate debt securities [Member]
Cash, Cash Equivalents and Short Term Investments [Line Items]
Cost of cash, cash equivalents and short term investments	6,709	6,682
Gross unrealized gains on cash, cash equivalents and short term investments	25	35
Gross unrealized losses on cash, cash equivalents and short term investments	(42)	(33)
Estimated fair value of cash, cash equivalents and short term investments	6,692	6,684
Cash [Member]
Cash, Cash Equivalents and Short Term Investments [Line Items]
Cost of cash, cash equivalents and short term investments	12,471	9,660
Gross unrealized gains on cash, cash equivalents and short term investments	0	0
Gross unrealized losses on cash, cash equivalents and short term investments	0	0
Estimated fair value of cash, cash equivalents and short term investments	12,471	9,660
Money market account [Member]
Cash, Cash Equivalents and Short Term Investments [Line Items]
Cost of cash, cash equivalents and short term investments	149	112
Gross unrealized gains on cash, cash equivalents and short term investments	0	0
Gross unrealized losses on cash, cash equivalents and short term investments	0	0
Estimated fair value of cash, cash equivalents and short term investments	$ 149	$ 112

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events, for cash, cash equivalents and short term investments

No definition available.

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- Definition

Cost of cash, cash equivalents and short term investments.

+ References

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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