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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Deposits (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Cash |  |
Deposit with non-insured institutions | $ 33.3 |
Guyanese dollars |  |
Cash |  |
Cash (in GYD) | $ 12.6 | $ 7.5
Minimum | Corporate bonds |  |
Cash |  |
Investment maturity term | 3 months |
Maximum | Corporate bonds |  |
Cash |  |
Investment maturity term | 1 year |

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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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