Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 28, 2020	Mar. 31, 2021	Mar. 28, 2020
Disaggregation Of Revenue [Line Items]
Revenue	$ 461,785	$ 359,603	$ 890,836	$ 715,713
Recurring revenue
Disaggregation Of Revenue [Line Items]
Revenue	414,845	315,862	799,803	621,230
Perpetual license
Disaggregation Of Revenue [Line Items]
Revenue	6,922	8,218	15,385	17,216
Professional services
Disaggregation Of Revenue [Line Items]
Revenue	$ 40,018	$ 35,523	$ 75,648	$ 77,267