Operating Segment and Geographical Information - Location of Identifiable Assets Other Than Acquired Intangible Asset and Liabilities (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 HKD ($) segment	Dec. 31, 2018 HKD ($)
Segment Reporting Information [Line Items]
Number of geographic reportable segments \| segment	3
Consolidated total liabilities	$ 10,748	$ 13,130
Continuing Operations [Member] \| Reportable Geographical Components [Member]
Segment Reporting Information [Line Items]
Consolidated total assets before intangible asset	187,707	440,727
Consolidated total liabilities	10,748	9,454
Continuing Operations [Member] \| Reportable Geographical Components [Member] \| Hong Kong [Member]
Segment Reporting Information [Line Items]
Consolidated total assets before intangible asset	184,061	437,081
Consolidated total liabilities	10,748	9,454
Continuing Operations [Member] \| Reportable Geographical Components [Member] \| United States [Member]
Segment Reporting Information [Line Items]
Consolidated total assets before intangible asset	$ 3,646	$ 3,646

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

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19-26)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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