Income Taxes - Summary of Reconciliation of Beginning and Ending Balance of Gross Unrecognized Tax Benefit (Detail) - USD ($) $ in Thousands	12 Months Ended
Oct. 31, 2016	Oct. 31, 2015
Income Tax Disclosure [Abstract]
Beginning balance	$ 132,054	$ 124,102
Increases in unrecognized tax benefits related to prior year tax positions	7,205	10,922
Decreases in unrecognized tax benefits related to prior year tax positions	(43,944)	(7,526)
Increases in unrecognized tax benefits related to current year tax positions	13,880	13,232
Decreases in unrecognized tax benefits related to settlements with taxing authorities	(333)	0
Reductions in unrecognized tax benefits due to lapse of applicable statute of limitations	(2,659)	(5,996)
Increases in unrecognized tax benefits acquired	49	976
Changes in unrecognized tax benefits due to foreign currency translation	290	(3,656)
Ending Balance	$ 106,542	$ 132,054

Unrecognized Tax Benefits Acquisitions

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Unrecognized tax benefits, period increase decrease, due to foreign currency translation

+ References

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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