Financial Statement Details - Other Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financial Statement Details [Abstract]
Prepaid preclinical and clinical trial services - with related party (Note 9)	$ 2,289	$ 4,075
Restricted cash	179	179
Security deposit	113	113
Other	21	19
Other Assets Noncurrent	$ 2,602	$ 4,386

Financial statement details.

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Prepaid preclinical and clinical trial services with related party in other assets.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

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