REGULATORY REQUIREMENTS (Details) $ in Thousands	Dec. 31, 2020 HKD ($)
Futu Securities (Hong Kong) Limited
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	$ 2,453,687
Requirement	1,286,263
Excess	1,167,424
Futu Inc
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	78,597
Requirement	11,945
Excess	66,652
Futu Clearing Inc
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	131,415
Requirement	1,938
Excess	129,477
Futu Singapore pte Ltd.
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	56,775
Requirement	586
Excess	56,189
Futu Insurance Brokers (Hong Kong) Limited
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	2,034
Requirement	500
Excess	$ 1,534

- Definition

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.

+ References

No definition available.

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- Definition

Amount of net capital in excess of minimum required net capital, calculated under Aggregate Indebtedness Standard.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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- Definition

Minimum amount of net capital required to be maintained by broker-dealer subsidiary to engage in security transaction, calculated under Aggregate Indebtedness Standard.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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- Definition

Amount of net capital of broker-dealer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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