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INVESTMENT IN EQUITY SECURITIES (Details Textual) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2015 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2015
Schedule of Investments [Line Items] |  |  |  |  |
Cost method investment |  | $ 0 |  |  |
Fair value of investment |  |  |  | $ 0 |
Loss on write down investment in equity securities |  | $ 0 | $ 0 | 579,000 |
Additional impairment loss |  |  |  |  | $ 26,000
Mevion Medical Systems Inc |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Fair value of investment | $ 600,000 |  |  |  | 579,000
Loss on write down investment in equity securities | $ 2,114,000 |  |  | $ 579,000 | $ 2,140,000

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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References No definition available. + Details
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562 + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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