Financial Assets and Liabilities - Summary of Cash Cash Equivalents and Investments (Detail) - USD ($) $ in Thousands	Oct. 31, 2016	Oct. 31, 2015
Cash Equivalents [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	$ 504,972	$ 239,473
Gross Unrealized Gains	0	0
Gross Unrealized Losses Less than 12 Months	0	(1)
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	504,972	239,472
Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	140,676	128,774
Gross Unrealized Gains	60	33
Gross Unrealized Losses Less than 12 Months	(41)	(60)
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	140,695	128,747
Other Long-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Non-marketable equity securities, Cost	9,756	10,277
Gross Unrealized Gains	0	0
Gross Unrealized Losses Less Than 12Months	0	0
Gross Unrealized Loss Position 12Months Or Longer	0	0
Non-marketable equity securities	9,756	10,277
Money Market Funds (U.S.) \| Cash Equivalents [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	499,274	233,839
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	499,274	233,839
Commercial Paper [Member] \| Cash Equivalents [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	1,498	1,834
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	1,498	1,834
Commercial Paper [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	25,430	12,129
Gross Unrealized Gains	1	0
Gross Unrealized Losses Less than 12 Months	0	0
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	25,431	12,129
US Government Agency Securities [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	13,607	12,615
Gross Unrealized Gains	4	3
Gross Unrealized Losses Less than 12 Months	(8)	(4)
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	13,603	12,614
Municipal Bonds [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost		1,403
Gross Unrealized Gains		1
Gross Unrealized Losses Less than 12 Months		(1)
Gross Unrealized Losses 12 Months or Longer		0
Estimated Fair Value		1,403
Certificates of Deposit [Member] \| Cash Equivalents [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	4,200	3,500
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	4,200	3,500
Certificates of Deposit [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	12,849	9,800
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	12,849	9,800
Corporate Debt Securities [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	58,753	67,201
Gross Unrealized Gains	43	27
Gross Unrealized Losses Less than 12 Months	(18)	(40)
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	58,778	67,188
Asset-backed Securities [Member] \| Cash Equivalents [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost		300
Gross Unrealized Gains		0
Gross Unrealized Losses Less than 12 Months		(1)
Gross Unrealized Losses 12 Months or Longer		0
Estimated Fair Value		299
Asset-backed Securities [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	22,146	24,619
Gross Unrealized Gains	12	2
Gross Unrealized Losses Less than 12 Months	(12)	(13)
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	22,146	24,608
Non-U.S. Government Agency Securities [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	3,403	1,007
Gross Unrealized Gains	0	0
Gross Unrealized Losses Less than 12 Months	(3)	(2)
Gross Unrealized Losses 12 Months or Longer	0	0
Estimated Fair Value	3,400	1,005
Others [Member] \| Short-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Available-for-sale Securities, Cost	4,488
Gross Unrealized Gains	0
Gross Unrealized Losses Less than 12 Months	0
Gross Unrealized Losses 12 Months or Longer	0
Estimated Fair Value	4,488
Non-Marketable Equity Securities [Member] \| Other Long-term Investments [Member]
Cash, Cash Equivalents and Investments [Line Items]
Non-marketable equity securities, Cost	9,756	10,277
Gross Unrealized Gains	0	0
Gross Unrealized Losses Less Than 12Months	0	0
Gross Unrealized Loss Position 12Months Or Longer	0	0
Non-marketable equity securities	$ 9,756	$ 10,277

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Securities Owned Not Readily Marketable Accumulated Gross Unrealized Gain Before Tax

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Securities Owned Not Readily Marketable Continuous Unrealized Loss Position 12Months Or Longer Accumulated Loss

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Securities Owned Not Readily Marketable Continuous Unrealized Loss Position Less Than 12Months Accumulated Loss

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Securities Owned Not Readily Marketable, Cost

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
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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.

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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.

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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.

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Aggregate carrying value of owned private equity or other securities for which a quoted market price is not readily determinable, the value of which has been determined by management based upon fair value methods, including pricing of similar securities and valuation techniques and is included in the schedule of financial condition or the balance sheet.

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