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MARKETABLE SECURITIES (Details) - USD ($) | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Fair Value [Member] |  |
Other Investment Not Readily Marketable [Line Items] |  |
Certificates of deposit | $ 2,986,000 |
Government securities | 13,054,000 |
Fixed income mutual funds | 11,541,000 | $ 14,325,000
Corporate bonds and notes | 178,000 | 801,000
Total marketable securities | 27,759,000 | 15,126,000
Cost Basis [Member] |  |
Other Investment Not Readily Marketable [Line Items] |  |
Certificates of deposit | 3,000,000 |
Government securities | 13,068,000 |
Fixed income mutual funds | 12,580,000 | 14,462,000
Corporate bonds and notes | 192,000 | 813,000
Total marketable securities | 28,840,000 | 15,275,000
Gross Unrealized Gains [Member] |  |
Other Investment Not Readily Marketable [Line Items] |  |
Certificates of deposit |  |
Government securities |  |
Fixed income mutual funds |  |
Corporate bonds and notes |  |
Total marketable securities |  |
Gross Unrealized Losses [Member] |  |
Other Investment Not Readily Marketable [Line Items] |  |
Certificates of deposit | (14,000) |
Government securities | (14,000) |
Fixed income mutual funds | (1,039,000) | (137,000)
Corporate bonds and notes | (14,000) | (12,000)
Total marketable securities | $ (1,081,000) | $ (149,000)

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