Operating Segment and Geographical Information - Reconciliation of Reportable Segment Assets and Liabilities (Details) - HKD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets
Current assets	$ 187,284	$ 441,665
Intangible asset	438	438
Consolidated total assets	188,145	563,439
Liabilities
Tax liabilities	9,407	8,678
Consolidated total liabilities	10,748	13,130
Continuing Operations [Member] \| Reportable Geographical Components [Member]
Assets
Current assets	187,284	439,941
Non-current financial assets	423	786
Consolidated total assets before intangible asset	187,707	440,727
Intangible asset	438	438
Consolidated total assets	188,145	441,165
Liabilities
Liabilities excluding tax liabilities	1,341	776
Tax liabilities	9,407	8,678
Consolidated total liabilities	$ 10,748	$ 9,454

Sum of the carrying amounts as of the balance sheet date of all assets except intangibles that are recognized.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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