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CASH AND CASH EQUIVALENTS, AND SHORT AND LONG-TERM INVESTMENTS (Tables) | 12 Months Ended
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Dec. 31, 2017
CASH AND CASH EQUIVALENTS, AND SHORT AND LONG-TERM INVESTMENTS |
Schedule of cash and cash equivalents and investments |
|  | 2017 |  | 2016 |
Cash |  | 10,439 |  | 9,412 |
Banks and immediately available investments |  | 2,544,899 |  | 5,053,971 |
Cash and cash equivalents |  | 2,555,338 |  | 5,063,383 |
|  | 2017 |  | 2016 |
Held for trading |  | 821,518 |  | 1,024,411 |
Short-term investments |  | 821,518 |  | 1,024,411 |

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