Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Fair Value Of Financial Instruments [Line Items]
Cash and cash equivalents	$ 38,868,000	$ 29,906,000
Restricted cash	316,000	316,000
Short-term investments	$ 0	19,978,000
Fair value of note payable to related party, description	The fair value measurement of debt instruments is based on a discounted cash flow model and is sensitive to the change in yield (Level 3 in the fair value hierarchy
Money Market Funds
Fair Value Of Financial Instruments [Line Items]
Cash and cash equivalents	$ 38,900,000	29,900,000
Restricted cash	$ 300,000	$ 300,000