LONG-TERM INVESTMENTS Additional Information (Details) - HKD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Jan. 31, 2019
Schedule of Equity Method Investments [Line Items]
Equity method investments (1)	$ 7,798	$ 0	$ 6,709
Impairment provision of equity method investments	0		$ 5,888
Equity investments without readily determinable fair values (2)	15,596
Impairment provision of equity investments without readily determinable fair values	$ 0	$ 0
TH Fund LP
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest (as a percent)	10.00%		20.00%
Newflow Amity Fund I, LP
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest (as a percent)	2.75%

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security without readily determinable fair value.

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Amount of cumulative impairment loss on investment in equity security without readily determinable fair value.

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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.

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