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7. MARKETABLE SECURITIES (Details Narrative) - Bank Certificate Of Deposits [member] | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Bottom Of Range [Member] |  |  |
Disclosure of Investment Securities [line items] |  |  |
Investment rate remunerated at percentage of rate for interbank deposits | 101.95% | 102.00% | 102.01%
Bottom Of Range [Member] | Debentures [Member] |  |  |
Disclosure of Investment Securities [line items] |  |  |
Investment rate remunerated at percentage of rate for interbank deposits | 108.25% | 104.25% | 104.25%
Top of Range [Member] |  |  |
Disclosure of Investment Securities [line items] |  |  |
Investment rate remunerated at percentage of rate for interbank deposits | 113.00% | 111.25% | 112.00%
Top of Range [Member] | Debentures [Member] |  |  |
Disclosure of Investment Securities [line items] |  |  |
Investment rate remunerated at percentage of rate for interbank deposits | 113.00% | 151.00% | 161.54%

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