Goodwill and Intangible Assets - Intangible Assets Balances (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Mar. 31, 2022	Sep. 30, 2021
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 66,130	$ 19,630
Accumulated amortization	(3,637)	(1,368)
Net book value	$ 62,493	$ 18,262
Developed Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average Amortization period in years	15 years	16 years
Gross carrying amount	$ 50,020	$ 19,120
Accumulated amortization	(2,745)	(1,361)
Net book value	$ 47,275	$ 17,759
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average Amortization period in years	10 years	2 years
Gross carrying amount	$ 15,210	$ 510
Accumulated amortization	(792)	(7)
Net book value	$ 14,418	$ 503
Tradenames & Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average Amortization period in years	3 years
Gross carrying amount	$ 900
Accumulated amortization	(100)
Net book value	$ 800