Accounts Receivable, Net and Unbilled Receivables - Schedule of Accounts Receivable, Net and Unbilled Receivables (Details) (Parenthetical) - USD ($) $ in Millions	Jul. 31, 2019	Oct. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Long-term investments and receivables, net	$ 4.2	$ 9.4
Government [Member]
Accounts Notes And Loans Receivable [Line Items]
U.S. government accounts receivable, including unbilled receivables	$ 1.0	$ 2.3

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle) and amount due to the Entity from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such investments and receivables to an amount that approximates their net realizable value.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LongTermInvestmentsAndReceivablesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant