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Liabilities Assumed Abstract [Abstract]

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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 assets acquired at the acquisition date.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of deferred revenue expected to be recognized as such within one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Business Combinations - Purchase Price Allocation (Details) - USD ($) $ in Thousands	Oct. 01, 2021	Jan. 22, 2021	Jun. 30, 2022	Sep. 30, 2021
Assets Acquired
Goodwill			$ 2,259,951	$ 2,216,553
Threat Stack, Inc
Assets Acquired
Cash, cash equivalents, and restricted cash	$ 912
Deferred tax assets	13,366
Other tangible assets acquired, at fair value	$ 5,481
Identifiable intangible assets useful life	5 years
Goodwill	$ 43,956
Total assets acquired	79,515
Liabilities assumed
Deferred revenue	(10,591)
Total liabilities assumed	(10,591)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net, Total	68,924
Threat Stack, Inc \| Developed Technology Rights
Assets Acquired
Identifiable intangible assets:	$ 11,400
Identifiable intangible assets useful life	5 years
Threat Stack, Inc \| Customer Relationships
Assets Acquired
Identifiable intangible assets:	$ 4,400
Identifiable intangible assets useful life	5 years
Volterra, Inc.
Assets Acquired
Cash, cash equivalents, and restricted cash		$ 14,012
Other tangible assets acquired, at fair value		$ 7,499
Identifiable intangible assets useful life		6 years 11 months 12 days
Goodwill		$ 350,863
Total assets acquired		432,374
Liabilities assumed
Total liabilities assumed		(5,233)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net, Total		427,141
Volterra, Inc. \| Developed Technology Rights
Assets Acquired
Identifiable intangible assets:		$ 59,500
Identifiable intangible assets useful life		7 years
Volterra, Inc. \| Customer Relationships
Assets Acquired
Identifiable intangible assets:		$ 500
Identifiable intangible assets useful life		1 year