13. STOCK-BASED COMPENSATION (Details)	12 Months Ended
Dec. 31, 2020 $ / shares shares
Share-based Payment Arrangement [Abstract]
Number of option and warrants outstanding, beginning balance \| shares	135,100
Number of option and warrants granted and vested \| shares	0
Number of option and warrants exercised \| shares	0
Number of option and warrants expired/cancelled \| shares	(13,500)
Number of option and warrants outstanding, ending balance \| shares	121,600
Weighted-average exercise price of option and warrants outstanding, beginning balance \| $ / shares	$ 7.21
Weighted-average exercise price of option and warrants granted and vested \| $ / shares	.00
Weighted-average exercise price of option and warrants exercised \| $ / shares	.00
Weighted-average exercise price of option and warrants expired/cancelled \| $ / shares	8.20
Weighted-average exercise price of option and warrants outstanding, ending balance \| $ / shares	$ 7.09
Range of exercise price per common share, beginning balance	$3.57 - $9.9
Range of exercise price per common share expired/cancelled	$7.20-$9.90
Range of exercise price per common share, ending balance	$3.57 - $7.27

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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.

+ 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)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Net number of share options (or share units) granted during the period.

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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)(1)
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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
-Topic 718
-SubTopic 10
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-Paragraph 2
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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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