SUMMARY OF SIGNIFICANT ACCOUNTING - BUSINESS ACQUISITIONS - Purchase price allocation (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Cash and cash equivalents	$ 339,611
Cash-segregated for regulatory purpose	22,094,198
Other current assets	5,098,900
Property, plant and equipment	5,581
Intangible assets
Operating License	6,900,000
Goodwill	2,421,403	$ 2,421,403
Other current liabilities	26,062,403
Deferred tax liabilities	1,449,000
Total purchase price	$ 9,348,290
Minimum
Business Acquisition [Line Items]
Useful life (in years)	3 years
Maximum
Business Acquisition [Line Items]
Useful life (in years)	5 years

The amount of cash segregated for regulatory purpose recognized as of the acquisition date.

No definition available.

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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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No definition available.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences assumed at the acquisition date.

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Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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