Summary of Significant Accounting Policies and Select Balance Sheet Information - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment [Line Items]
Less: Accumulated depreciation	$ (47,716)	$ (42,962)
Property and equipment, net	30,090	30,103
Land [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	4,419	4,419
Laboratory Fixtures and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 29,482	28,600
Laboratory Fixtures and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	3 years
Laboratory Fixtures and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	10 years
Building and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 26,573	25,638
Building and Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	3 years
Building and Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	20 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 6,499	4,836
Leasehold Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	5 years
Leasehold Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	10 years
Office Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 8,713	7,334
Office Furniture and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	3 years
Office Furniture and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	10 years
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 2,120	$ 2,238