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FAIR VALUE MEASUREMENTS (Details 2) (Corporate notes, USD $) In Thousands, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012
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Corporate notes |  |
Marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | $ 31,654 | $ 27,045
Less Than 12 Months - Gross Unrealized Losses | (22) | (8)
Total - Estimated Fair Value | 31,654 | 27,045
Total - Gross Unrealized Losses | $ (22) | $ (8)

X
- Definition Amount of gross unrealized loss on securities classified as available-for-sale securities that have been in a loss position as of the reporting date. + References No definition available. + Details
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- Definition Amount of gross unrealized loss on securities classified as available-for-sale securities that have been in a loss position for less than twelve months as of the reporting date. + References No definition available. + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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