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Property and Equipment, net - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Depreciation $ 1.1 $ 1.7 $ 3.5 $ 5.5
Write down no longer use in property and equipment   $ 0.6 $ 2.8 $ 0.6