Business Combinations - Additional Information (Details) - USD ($) $ in Thousands		9 Months Ended
	Dec. 11, 2017	Jul. 31, 2018	Jul. 31, 2017	Oct. 31, 2017
Business Acquisition [Line Items]
Payments to acquire businesses, net of cash, cash equivalents and short-term investments		$ 631,100
Goodwill		3,138,666		$ 2,706,974
Payment to acquire business net of cash acquired		646,687	$ 187,624
Black Duck Software
Business Acquisition [Line Items]
Payments to acquire businesses, net of cash, cash equivalents and short-term investments		544,000
Consideration transfered	$ 565,100	565,088
Goodwill		396,346
Identifiable intangibles assets acquired		178,000
Acquisition-related costs		13,900
Fair value of equity awards acquired		15,600
Fair value of assumed equity awards allocated to purchase consideration		1,588
Fair value of stock options assumed		14,000
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Goodwill		38,400
Identifiable intangibles assets acquired		50,200
Acquisition-related costs		3,400
Payment to acquire business net of cash acquired		$ 87,100
Minimum | Black Duck Software
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life		1 year
Minimum | Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life		1 year
Maximum | Black Duck Software
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life		10 years
Maximum | Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life		7 years