INCOME TAXES - Unrecognized tax benefits (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Unrecognized tax benefits
Balance as of December 31, 2019	$ 881,796
Increase related to prior year tax positions	13,281
Decrease related to prior year tax positions	(17,656)
Increase related to current year tax positions	30,675
Balance as of December 31, 2020	908,095
Amount of interest and penalties related to uncertain tax positions	0	$ 0
Total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate	$ 0	$ 0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 10B
-URI http://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Name Accounting Standards Codification
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