Commitments and Contingencies - Additional Information (Detail) $ in Thousands	Sep. 30, 2021 USD ($)	Sep. 30, 2021 GBP (£)	Dec. 31, 2020 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Potential payable amount over the agreement terms based on minimum purchase obligation	$ 213,000
Accrued expenses and other current liabilities	289,684		$ 198,641
Further Indication for AMR101 \| Marketing Approval In Europe
Commitments And Contingencies Disclosure [Line Items]
Potential aggregate stock or cash payment \| £		£ 7,500,000
Accrued expenses and other current liabilities	12,000
Further Indication for AMR101 \| Potential Marketing Approval 1
Commitments And Contingencies Disclosure [Line Items]
Aggregate stock or cash payment upon potential market approval	6,700	5,000,000
Further Indication for AMR101 \| Potential Marketing Approval 2
Commitments And Contingencies Disclosure [Line Items]
Aggregate stock or cash payment upon potential market approval	$ 6,700	£ 5,000,000