Assets Acquired [Abstract]

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Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Operating Lease, Lease Liabilities

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- Definition

Business Combination, Recognized Identifiable Asset Acquired and Liability Assumed, Operating Lease, Right-Of-Use Assets

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- Definition

Fair Value of intangible Assets [Abstract]

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- Definition

Liabilities Assumed Abstract [Abstract]

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- Definition

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 other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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- Definition

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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- Definition

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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- Definition

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 of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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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	Jan. 24, 2020	May 08, 2019	Jun. 30, 2020	Sep. 30, 2019
Fair value of tangible assets:
Goodwill			$ 1,858,966	$ 1,065,379
Shape Security, Inc.
Assets acquired
Cash and cash equivalents	$ 53,934
Fair value of tangible assets:
Accounts receivable	21,077
Deferred tax assets	24,619
Operating lease right-of-use assets	29,644
Other tangible assets	$ 22,571
Identifiable intangible assets useful life	6 years 6 months
Goodwill	$ 799,611
Total assets acquired	1,101,956
Liabilities assumed
Deferred revenue	(39,000)
Operating lease liabilities	(30,773)
Other assumed liabilities	(18,571)
Total liabilities assumed	(88,344)
Net assets acquired	1,013,612
Shape Security, Inc. \| Developed Technology Rights
Fair value of tangible assets:
Identifiable intangible assets:	$ 120,000
Identifiable intangible assets useful life	7 years
Shape Security, Inc. \| Customer Relationships
Fair value of tangible assets:
Identifiable intangible assets:	$ 21,000
Identifiable intangible assets useful life	4 years
Shape Security, Inc. \| Trade Names
Fair value of tangible assets:
Identifiable intangible assets:	$ 9,500
Identifiable intangible assets useful life	5 years
F5 Networks Acquisition of Nginx
Assets acquired
Cash and cash equivalents		$ 29,911
Fair value of tangible assets:
Other tangible assets		$ 23,699
Identifiable intangible assets useful life		8 years 1 month 6 days
Goodwill		$ 503,414
Total assets acquired		646,324
Liabilities assumed
Other assumed liabilities		(9,116)
Total liabilities assumed		(9,116)
Net assets acquired		637,208
F5 Networks Acquisition of Nginx \| Developed Technology Rights
Fair value of tangible assets:
Identifiable intangible assets:		$ 62,500
Identifiable intangible assets useful life		7 years
F5 Networks Acquisition of Nginx \| Customer Relationships
Fair value of tangible assets:
Identifiable intangible assets:		$ 12,000
Identifiable intangible assets useful life		15 years
F5 Networks Acquisition of Nginx \| Trade Names
Fair value of tangible assets:
Identifiable intangible assets:		$ 14,500
Identifiable intangible assets useful life		7 years
F5 Networks Acquisition of Nginx \| Non-competition Agreements
Fair value of tangible assets:
Identifiable intangible assets:		$ 300
Identifiable intangible assets useful life		2 years