Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Commitments [Line Items]
Contingent liabilities	$ 0
Future commitments	100,200,000
Commitments expected to be incurred in remaining fiscal year 2021	85,000,000.0
Technology License Commitments
Other Commitments [Line Items]
Milestone payments	$ 0	$ 0