SHARE-BASED COMPENSATION - Restricted Shares Plan (Details) - Restricted shares $ / shares in Units, $ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2023 HKD ($) $ / shares shares	Dec. 31, 2022 $ / shares shares	Dec. 31, 2021 $ / shares shares	Dec. 31, 2023 USD ($)
Shares awarded number
Outstanding at beginning	26,692,248	16,961,864	6,067,400
Vested	(5,683,896)	(3,138,104)	(929,672)
Granted	8,769,800	14,357,520	12,105,712
Forfeited	(2,500,424)	(1,489,032)	(281,576)
Outstanding at end	27,277,728	26,692,248	16,961,864
Weighted-average grant date fair value per share
Outstanding at beginning \| $ / shares	$ 5.3631	$ 5.6793	$ 4.6827
Vested \| $ / shares	5.0877	5.7371	4.6827
Granted \| $ / shares	6.1047	5.0877	5.7371
Forfeited \| $ / shares	5.2052	5.5209	5.4426
Outstanding at end \| $ / shares	$ 5.6734	$ 5.3631	$ 5.6793
Unrecognized compensation expenses related to the restricted shares	$ 1,130,550			$ 144,740
Unrecognized compensation expenses related to the restricted shares expected to be recognized over a weighted-average period	3 years 10 months 24 days
2019 Share Incentive Plan
Shares awarded number
Granted	8,769,800	14,357,520	12,105,712

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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