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Business Combinations - Narrative (Details) - USD ($) $ in Millions			12 Months Ended
	Oct. 01, 2021	Jan. 22, 2021	Sep. 30, 2021
Threat Stack, Inc.
Business Acquisition [Line Items]
Total Purchase Price	$ 68.9
Identifiable Intangible Assets Useful Life	5 years
Volterra, Inc.
Business Acquisition [Line Items]
Total Purchase Price		$ 427.2
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			$ 9.5
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
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