13. STOCK-BASED COMPENSATION (Details)	3 Months Ended
Mar. 31, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Option and Warrants Outstanding, Beginning balance \| shares	2,518,000
Number of Option and Warrants Granted and Vested \| shares	(245,000)
Number of Option and Warrants Expired \| shares	(12,500)
Number of Option and Warrants Outstanding, Ending Balance \| shares	2,260,500
Weighted- Average Exercise price of Option and Warrants, Beginning balance \| $ / shares	$ 0.97
Weighted- Average Exercise price of Option and Warrants, Granted and vested during the period \| $ / shares	0.71
Weighted- Average Exercise price of Option and Warrants, Expired \| $ / shares	1.78
Weighted- Average Exercise price of Option and Warrants, Ending Balance \| $ / shares	$ 0.99
Range of Exercise Price per Common Share, Granted and Vested	0.71
Range of Exercise Price per Common Share, Expired	1.78
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Price per Common Share, Beginning Balance	0.71
Range of Exercise Price per Common Share, Ending Balance	0.71
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Price per Common Share, Beginning Balance	4.80
Range of Exercise Price per Common Share, Ending Balance	4.80

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)-(4)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Weighted average price of options that were either forfeited or expired.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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-Publisher FASB
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