The estimated forfeiture rate of the underlying shares over the option's term.

No definition available.

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- Definition

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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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809

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SHARE-BASED COMPENSATION - Fair value of options granted and compensation expenses (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021 HKD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021 USD ($)
Fair value of options granted estimation:
Risk-free interest rate (as a percent)			1.67%
Expected term (in years)	5 years	5 years	5 years
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%
Expected volatility (as a percent)	40.00%	40.00%	45.00%
Expected forfeiture rate (post-vesting) (as a percent)	15.00%	15.00%	15.00%
Minimum
Fair value of options granted estimation:
Risk-free interest rate (as a percent)	0.09%	0.27%
Maximum
Fair value of options granted estimation:
Risk-free interest rate (as a percent)	0.89%	0.36%
Share Options
Fair value of options granted estimation:
Unrecognized compensation expenses	$ 201,948			$ 25,897
Weighted-average period expected to be recognized for unrecognized compensation expense (in years)	3 years 11 months 15 days