Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Jun. 30, 2021	Sep. 30, 2020
Indefinite Lived Intangible Assets By Major Class [Line Items]
Cost	$ 52,777	$ 38,587
Accumulated Amortization	24,220	19,298
Net	$ 28,557	$ 19,289
Completed technologies
Indefinite Lived Intangible Assets By Major Class [Line Items]
Weighted Average Amortization Period	6 years 7 months 6 days	6 years 4 months 24 days
Cost	$ 31,621	$ 20,341
Accumulated Amortization	11,860	9,416
Net	$ 19,761	$ 10,925
Customer relationships
Indefinite Lived Intangible Assets By Major Class [Line Items]
Weighted Average Amortization Period	4 years 7 months 6 days	4 years 9 months 18 days
Cost	$ 20,168	$ 17,628
Accumulated Amortization	11,825	9,390
Net	$ 8,343	$ 8,238
Trade names
Indefinite Lived Intangible Assets By Major Class [Line Items]
Weighted Average Amortization Period	4 years 8 months 12 days	4 years 6 months
Cost	$ 988	$ 618
Accumulated Amortization	535	492
Net	$ 453	$ 126