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.

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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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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 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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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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SHARE-BASED COMPENSATION - Restricted Shares Plan (Details) - Restricted shares $ / shares in Units, $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 HKD ($) $ / shares shares	Dec. 31, 2020 $ / shares shares	Dec. 31, 2019 shares	Dec. 31, 2021 USD ($)
Shares awarded number
Outstanding at beginning	6,067,400
Granted	12,105,712
Vested	(929,672)
Forfeited	(281,576)
Outstanding at end	16,961,864	6,067,400
Weighted-average grant date fair value per share
Outstanding at beginning \| $ / shares	$ 4.6827
Granted \| $ / shares	5.7371
Vested \| $ / shares	4.6827
Forfeited \| $ / shares	5.4426
Outstanding at end \| $ / shares	$ 5.6793	$ 4.6827
Unrecognized compensation expenses related to the restricted shares	$ 694,749			$ 89,092
Unrecognized compensation expenses related to the restricted shares expected to be recognized over a weighted-average period	4 years 7 months 20 days
2019 Share Incentive Plan
Shares awarded number
Granted	12,105,712	6,067,400	0