Fair Values on Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair value of financial assets and liabilities
Total financial assets	$ 103,625	$ 59,592
Total financial assets	103,625	59,592
Money market funds
Fair value of financial assets and liabilities
Total short-term investments	6,203	8,860
Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	103,203
United States government agency securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	30,683	15,561
Corporate debt securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	66,317	35,171
Warrant \| Other Assets
Fair value of financial assets and liabilities
Warrants	422
Level 1
Fair value of financial assets and liabilities
Total financial assets	6,203	8,860
Total financial assets	6,203	8,860
Level 1 \| Money market funds
Fair value of financial assets and liabilities
Total short-term investments	6,203	8,860
Level 1 \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	6,203
Level 2
Fair value of financial assets and liabilities
Total financial assets	97,000	50,732
Total financial assets	97,000	50,732
Level 2 \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	97,000
Level 2 \| United States government agency securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	30,683	15,561
Level 2 \| Corporate debt securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	66,317	$ 35,171
Level 3
Fair value of financial assets and liabilities
Total financial assets	422
Total financial assets	422
Level 3 \| Warrant \| Other Assets
Fair value of financial assets and liabilities
Warrants	$ 422

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ References

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-Publisher FASB
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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