Supplemental Disclosures to the Unaudited Condensed Consolidated Balance Sheets and Unaudited Condensed Consolidated Statements of Cash Flows - Summary of Cash and Cash Equivalents Reconciliation (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Cash And Cash Equivalents [Abstract]
Cash and cash equivalents	$ 16,801	$ 10,364
Restricted cash	0	0
Total cash, cash equivalents and restricted cash	$ 16,801	$ 10,364	$ 1,894	$ 325