Balance Sheet Components - Property and Equipment, net (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 4,116	$ 4,116
Less: Accumulated depreciation and amortization	(2,402)	(2,308)
Impairment loss	(498)
Property and equipment, net	1,216	1,808
Equipment and Furniture [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,442	1,442
Buildings, Leasehold and Building Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,674	$ 2,674

Accumulated impairment loss property plant and equipment.

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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-Publisher FASB
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- Definition

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

+ References

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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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- 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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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