Name:	futu_DecreaseInPreTaxIncomeDueToReasonablyPossibleIncreaseInDesignatedRiskComponent
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Period Type:	duration

The increase in a pre-tax profit as a result of an decrease in a designated risk component that was reasonably possible at the end of the reporting period. Excludes defined benefit plan obligations.

No definition available.

Name:	futu_IncreaseInPreTaxIncomeDueToReasonablyPossibleDecreaseInDesignatedRiskComponent
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The reasonably possible percentage of the decrease in the designated risk component used to determine the value of the financial instrument. Excludes defined benefit plan obligations.

No definition available.

Name:	futu_PercentageOfReasonablyPossibleDecreaseInRiskAssumption
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Data Type:	dtr-types:percentItemType
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The reasonably possible percentage of the increase in the designated risk component used to determine the value of the financial instrument. Excludes defined benefit plan obligations.

No definition available.

Name:	futu_PercentageOfReasonablyPossibleIncreaseInRiskAssumption
Namespace Prefix:	futu_
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Amount of net assets (liabilities).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 30
-Topic 205
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479910/205-30-50-1

Name:	us-gaap_AssetsNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481027/954-310-50-2

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The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

No definition available.

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Data Type:	dtr-types:percentItemType
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Aggregate gain on all derivative instruments recognized in earnings during the period, before tax effects.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A