Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2019	Oct. 31, 2018
Capitalized Contract Cost [Line Items]
Revenue recognized that was previously deferred	$ 39.4
Remaining performance obligations	$ 1,070.0
Percentage of remaining performance obligation expected to be recognized within next twelve months	80.00%
Capitalized Contract Acquisition Costs
Capitalized Contract Cost [Line Items]
Capitalized contract acquisition costs	$ 12.4	$ 13.6
Amortization of capitalized contract acquisition costs	$ 4.1

Revenue, Remaining Performance Obligation Expected to Recognized in Next Twelve Months, Percentage

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
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+ References

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
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-Section 50
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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 8
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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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