CARES Act Loans and Foreign Wage Subsidy - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021	Jun. 30, 2020	Sep. 30, 2021	Dec. 31, 2020
Gain on extinguishment	$ 5,185,000		$ 5,185,000
Reductions to Payroll Expenses Under Foreign Wage Subsidy	$ 135,000		$ 434,000
CARES Act
Proceeds from promissory notes		$ 5,300,000		$ 5,100,000
Maturity period of loan			2 years
Interest rate on loan	1.00%		1.00%
Debt Instrument, Description			The terms of the Loans are two years with maturity dates in the second quarter of 2022 and they contain a fixed annual interest rate of 1%. In the third quarter of 2021, we were legally released from our obligation as our application was approved by the SBA. We recognized a gain on extinguishment of $5.2 million in the Condensed Consolidated Statement of Operations.
Gain on extinguishment	$ 5,200,000

Reductions to payroll expenses under foreign wage subsidy.

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