Accounts Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Concentration Risk [Line Items]
Unbilled receivables	$ 40,900	$ 26,100
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of period	17,580	3,963	$ 2,963
Provisions	2,700	18,221	1,701
Net Deductions	2,902	4,604	701
Balance at end of period	$ 17,378	$ 17,580	$ 3,963
One Unidentified Customer \| Customer Concentration Risk \| Accounts Receivable
Concentration Risk [Line Items]
Net accounts receivable percentage	10.00%
Two Unidentified Customers \| Customer Concentration Risk \| Accounts Receivable
Concentration Risk [Line Items]
Net accounts receivable percentage		23.00%
APC Region Customer
Allowance for Doubtful Accounts Receivable [Roll Forward]
Provisions		$ 13,700

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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