Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Disaggregation Of Revenue [Line Items]
Revenue		$ 462,474	$ 435,668	$ 1,425,422	$ 1,326,504
Recurring revenue
Disaggregation Of Revenue [Line Items]
Revenue	[1]	415,197	387,175	1,273,032	1,186,978
Perpetual license
Disaggregation Of Revenue [Line Items]
Revenue		8,203	7,259	26,211	22,644
Professional services
Disaggregation Of Revenue [Line Items]
Professional services		$ 39,074	$ 41,234	$ 126,179	$ 116,882

[1] Recurring revenue is comprised of on-premise subscription, perpetual support, SaaS, and cloud services revenue.