Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Business Combinations - Narrative (Details) - USD ($) $ in Thousands				12 Months Ended
	Oct. 01, 2021	Jan. 22, 2021	Jan. 24, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Goodwill, Other Increase (Decrease)				$ (1,227)	$ 6,170
Threat Stack, Inc.
Business Acquisition [Line Items]
Total Purchase Price	$ 68,900
Identifiable Intangible Assets Useful Life	5 years
Volterra, Inc.
Business Acquisition [Line Items]
Total Purchase Price		$ 427,200
Identifiable Intangible Assets Useful Life		6 years 11 months 12 days
Volterra, Inc. \| General and Administrative Expense
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs					$ 9,500
Shape Security, Inc.
Business Acquisition [Line Items]
Total Purchase Price			$ 1,000,000
Transaction Costs			$ 23,200
Identifiable Intangible Assets Useful Life			6 years 6 months
Shape Security, Inc. \| General and Administrative Expense
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs						$ 15,300
Developed Technology Rights \| Threat Stack, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life	5 years
Developed Technology Rights \| Volterra, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life		7 years
Developed Technology Rights \| Shape Security, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life			7 years
Customer Relationships \| Threat Stack, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life	5 years
Customer Relationships \| Volterra, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life		1 year
Customer Relationships \| Shape Security, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life			4 years
Trade Names \| Shape Security, Inc.
Business Acquisition [Line Items]
Identifiable Intangible Assets Useful Life			5 years