Summary of Long-Lived Assets by Geographical Areas (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Real estate properties under development	$ 190,492	$ 251,685
Property, plant and equipment	26,568	25,950
Right of use assets	9,695	4,078
Net book value	318,962	281,713
PRC (excluding Hong Kong)
Segment Reporting Information [Line Items]
Real estate properties under development	190,492	251,685
Property, plant and equipment	26,389	25,624
Real estate properties held for lease	92,207
Right of use assets	9,511	3,597
Hong Kong
Segment Reporting Information [Line Items]
Property, plant and equipment	179	326
Right of use assets	$ 184	$ 481

Real estate held for lease.

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- Definition

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

For banks, amount of real estate assets held for development or sale, net of associated liabilities.

+ References

No definition available.

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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.

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