Financial Assets and Liabilities - Short-term investments (Details) - Cash equivalents - USD ($) $ in Thousands	Apr. 30, 2019	Oct. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, cost	$ 206,438	$ 165,296
Gross unrealized gains	0	0
Gross unrealized losses less than 12 months	0	0
Gross unrealized losses 12 months or longer	0	0
Estimated fair value	206,438	165,296
Money market funds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, cost	206,438	165,296
Gross unrealized gains	0	0
Gross unrealized losses less than 12 months	0	0
Gross unrealized losses 12 months or longer	0	0
Estimated fair value	$ 206,438	$ 165,296

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Details

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