Summary of Significant Accounting Policies - Summary of Acquired Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 126,779	$ 95,775
Accumulated Amortization	43,582	35,532
Manufacturing Technologies, Core Products and Cell Lines [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	62,363	56,193
Accumulated Amortization	18,750	15,096
Tradenames, Licenses and Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	18,425	14,494
Accumulated Amortization	7,801	6,094
Customer Lists, Customer Relationships, and Supply Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	45,071	24,274
Accumulated Amortization	16,210	14,110
Government Grants [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	810	814
Accumulated Amortization	810	$ 232
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	110
Accumulated Amortization	$ 11