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FAIR VALUE MEASUREMENTS (Details 2) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
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Marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | $ 92,458 | $ 41,007
Less Than 12 Months - Gross Unrealized Losses | (60) | (19)
Total - Estimated Fair Value | 92,458 | 41,007
Total - Gross Unrealized Losses | (60) | (19)
Government-sponsored enterprise securities (due in less than 1 year) |  |
Marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | 401 | 3,947
Less Than 12 Months - Gross Unrealized Losses | (1) | (1)
Total - Estimated Fair Value | 401 | 3,947
Total - Gross Unrealized Losses | (1) | (1)
Government-sponsored enterprise securities (due in 1 to 2 years) |  |
Marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | 3,748 |
Less Than 12 Months - Gross Unrealized Losses | (3) |
Total - Estimated Fair Value | 3,748 |
Total - Gross Unrealized Losses | (3) |
Corporate notes (due in less than 1 year) |  |
Marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | 77,087 | 37,060
Less Than 12 Months - Gross Unrealized Losses | (38) | (18)
Total - Estimated Fair Value | 77,087 | 37,060
Total - Gross Unrealized Losses | (38) | (18)
Corporate notes (due in 1 to 2 years) |  |
Marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | 11,222 |
Less Than 12 Months - Gross Unrealized Losses | (18) |
Total - Estimated Fair Value | 11,222 |
Total - Gross Unrealized Losses | $ (18) |

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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 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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