Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disaggregation Of Revenue [Line Items]
Revenue	$ 457,721	$ 429,050
Recurring revenue
Disaggregation Of Revenue [Line Items]
Revenue	405,125	384,957
Perpetual license
Disaggregation Of Revenue [Line Items]
Revenue	8,468	8,463
Professional services
Disaggregation Of Revenue [Line Items]
Revenue	$ 44,128	$ 35,630

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details