Cash, Cash Equivalents and Short-Term Investments - Cash, Cash Equivalents and Short-Term Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Cash And Cash Equivalents [Abstract]
Cash	$ 4,189	$ 4,092
Cash equivalents	5,855	3,620
Restricted cash	600	600
Total cash and cash equivalents	10,644	8,312	$ 8,090	$ 10,531
Short-term investments		2,249
Total cash, cash equivalents and short-term investments	$ 10,644	$ 10,561