Income Taxes - Deferred Components of Benefit (Provision), Net for Income Taxes (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current benefit (provision), net for income taxes:
Total current benefit (provision), net for income taxes	$ 841,000
Deferred benefit (provision), net for income taxes:
Total benefit (provision), net for income taxes	841,000	$ 0
Singapore [Member]
Deferred benefit (provision), net for income taxes:
Total benefit (provision), net for income taxes	0	$ 0
Rest Of World [Member]
Current benefit (provision), net for income taxes:
Total current benefit (provision), net for income taxes	$ 841,000