REGULATORY REQUIREMENTS (Details) $ in Thousands	Dec. 31, 2019 HKD ($)
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	$ 1,557,940
Requirement	239,375
Excess	1,318,565
Futu Securities (Hong Kong) Limited
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	1,469,200
Requirement	235,481
Excess	1,233,719
Futu Inc
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	15,832
Requirement	1,947
Excess	13,885
Futu Clearing Inc
Regulatory Requirements, Disclosure [Line Items]
Net Capital/ Eligible Equity	72,908
Requirement	1,947
Excess	$ 70,961

- 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.

+ Details

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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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