Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Cash flow from operating activities:
Net income	$ 136,563	$ 266,826	$ 225,934
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization and depreciation	189,442	207,032	211,821
Stock-based compensation	108,294	97,583	86,400
Allowance for doubtful accounts	2,149	950	1,300
(Gain) loss on sale of investments	8	(18)	(109)
Write-down of long-term investments	1,300	0	0
Deferred income taxes	123,052	(14,037)	36,883
Net changes in operating assets and liabilities, net of acquired assets and liabilities:
Accounts receivable	2,296	(43,269)	(56,533)
Prepaid and other current assets	(28,955)	(37,641)	(23,106)
Other long-term assets	(40,236)	(3,770)	(16,259)
Accounts payable and accrued liabilities	137,631	18,977	27,568
Income taxes	19,665	7,098	(48,878)
Deferred revenue	(16,644)	86,904	50,139
Net cash provided by operating activities	634,565	586,635	495,160
Cash flows from investing activities:
Proceeds from sales and maturities of short-term investments	295,633	156,350	109,173
Purchases of short-term investments	(155,098)	(168,712)	(238,902)
Proceeds from sales of long-term investments	839	1,785	0
Purchases of long-term investments	0	(1,002)	0
Purchases of property and equipment	(70,328)	(66,909)	(86,965)
Cash paid for acquisitions and intangible assets, net of cash acquired	(259,202)	(60,056)	(340,153)
Capitalization of software development costs	(3,226)	(4,131)	(3,682)
Other	2,100	0	900
Net cash used in investing activities	(189,282)	(142,675)	(559,629)
Cash flows from financing activities:
Proceeds from credit facility	320,000	185,000	460,000
Repayment of debt	(380,625)	(185,000)	(330,425)
Issuances of common stock	126,337	125,283	109,764
Payments for taxes related to net share settlement of equity awards	(36,730)	(26,562)	(24,860)
Purchase of equity forward contract	(20,000)	0	(20,000)
Purchases of treasury stock	(380,000)	(400,000)	(260,000)
Other	(2,102)	(5,658)	3,451
Net cash used in financing activities	(373,120)	(306,937)	(62,070)
Effect of exchange rate changes on cash and cash equivalents	(427)	3,409	(23,035)
Net change in cash and cash equivalents	71,736	140,432	(149,574)
Cash and cash equivalents, beginning of year	976,620	836,188	985,762
Cash and cash equivalents, end of year	1,048,356	976,620	836,188
Supplemental disclosure of cash flow information:
Cash paid for income taxes during the year:	103,478	69,447	59,731
Interest payments during the year:	$ 7,095	$ 3,708	$ 2,710