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INVESTMENTS - (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Investments rollforward |  |  |
Proceeds from sale of investments | $ 1,266 | $ 6,769 | $ 2,895
Cost of purchase of marketable equity securities |  | 1,300 |
Marketable equity securities |  |  |
Investments rollforward |  |  |
Proceeds from sale of investments | $ 1,300 | $ 6,800 | $ 2,900

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- Definition Cash paid to purchase debt and equity securities, classified as operating activities, during the period; includes trading securities and any other investments classified as operating. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585 + Details
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