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MARKETABLE SECURITIES - Amortized cost basis, fair value and net unrealized gains on available-for-sale securities (Details) $ in Thousands | Dec. 31, 2018 USD ($)
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Marketable Securities: |
Amortized Cost Basis | $ 7,674
Fair Value | 7,665
Net Unrealized Losses | (9)
Municipal Obligations |
Marketable Securities: |
Amortized Cost Basis | 1,490
Fair Value | 1,490
Net Unrealized Losses | 0
Corporate Obligations |
Marketable Securities: |
Amortized Cost Basis | 6,184
Fair Value | 6,175
Net Unrealized Losses | $ (9)

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 + Details
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