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Marketable Securities (Details 2) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012
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Summary of Available-for-sale securities in unrealized loss position for other-than-temporary impairments |  |
Corporate debt securities, Gross Unrealized Losses |  | $ 50
Corporate debt securities, Fair Value |  | $ 2,500

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- Definition Amount of accumulated pre-tax unrealized loss before deducting unrealized gain on investments in available-for-sale securities recognized in Accumulated Other Comprehensive Income (AOCI). + 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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