Fair Values on Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair value of financial assets and liabilities
Total financial assets	$ 88,823	$ 103,625
Money market funds
Fair value of financial assets and liabilities
Total short-term investments	24,188	6,203
Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	87,999	103,203
United States government agency securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	16,047	30,683
Corporate debt securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	47,764	66,317
Warrant \| Other Assets
Fair value of financial assets and liabilities
Warrants	824	422
Level 1
Fair value of financial assets and liabilities
Total financial assets	24,188	6,203
Level 1 \| Money market funds
Fair value of financial assets and liabilities
Total short-term investments	24,188	6,203
Level 1 \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	24,188	6,203
Level 2
Fair value of financial assets and liabilities
Total financial assets	63,811	97,000
Level 2 \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	63,811	97,000
Level 2 \| United States government agency securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	16,047	30,683
Level 2 \| Corporate debt securities \| Short-term Investments
Fair value of financial assets and liabilities
Total short-term investments	47,764	66,317
Level 3
Fair value of financial assets and liabilities
Total financial assets	824	422
Level 3 \| Warrant \| Other Assets
Fair value of financial assets and liabilities
Warrants	$ 824	$ 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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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ 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.

+ References

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