SHARE-BASED COMPENSATION - Restricted Shares Plan (Details) - Restricted shares $ / shares in Units, $ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2022 HKD ($) $ / shares shares	Dec. 31, 2021 $ / shares shares	Dec. 31, 2020 $ / shares shares	Dec. 31, 2022 USD ($)
Shares awarded number
Outstanding at beginning	16,961,864	6,067,400
Granted	14,357,520	12,105,712	6,067,400
Vested	(3,138,104)	(929,672)
Forfeited	(1,489,032)	(281,576)
Outstanding at end	26,692,248	16,961,864	6,067,400
Weighted-average grant date fair value per share
Outstanding at beginning \| $ / shares	$ 5.6793	$ 4.6827
Granted \| $ / shares	5.0877	5.7371	$ 4.6827
Vested \| $ / shares	5.7371	4.6827
Forfeited \| $ / shares	5.5209	5.4426
Outstanding at end \| $ / shares	$ 5.3631	$ 5.6793	$ 4.6827
Unrecognized compensation expenses related to the restricted shares	$ 1,051,157			$ 134,821
Unrecognized compensation expenses related to the restricted shares expected to be recognized over a weighted-average period	4 years 3 months 29 days
2019 Share Incentive Plan
Shares awarded number
Granted	14,357,520	12,105,712	6,067,400

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.

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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