Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 27, 2020	Jun. 30, 2021	Jun. 27, 2020
Disaggregation Of Revenue [Line Items]
Revenue	$ 435,668	$ 351,721	$ 1,326,504	$ 1,067,434
Recurring revenue
Disaggregation Of Revenue [Line Items]
Revenue	387,175	310,621	1,186,978	931,852
Perpetual license
Disaggregation Of Revenue [Line Items]
Revenue	7,259	6,773	22,644	23,988
Professional services
Disaggregation Of Revenue [Line Items]
Revenue	$ 41,234	$ 34,327	$ 116,882	$ 111,594