Condensed Consolidated Statements of Cash Flows (USD $) In Thousands	6 Months Ended
Apr. 30, 2011	Apr. 30, 2010
Cash flow from operating activities:
Net income	$ 129,340	$ 172,335
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization and depreciation	64,998	50,218
Stock compensation	27,914	30,700
Allowance for doubtful accounts	723	(742)
Write-down of long-term investments	999
Gain on sale of investments	(50)	(2,420)
Deferred income taxes	(939)	(38,549)
Net changes in operating assets and liabilities, net of acquired assets and liabilities:
Accounts receivable	(28,904)	(20,626)
Prepaid and other current assets	(8,848)	(7,139)
Other long-term assets	(11,658)	(3,997)
Accounts payable and accrued liabilities	(69,320)	(68,672)
Income taxes	(40,890)	(29,645)
Deferred revenue	(6,510)	(45,235)
Net cash provided by operating activities	56,855	36,228
Cash flows from investing activities:
Proceeds from sales and maturities of short-term investments	63,648	188,650
Purchases of short-term investments	(49,435)	(131,748)
Purchases of property and equipment	(20,600)	(13,793)
Cash paid for acquisitions and intangible assets, net of cash acquired	(3,520)	(130,872)
Capitalization of software development costs	(1,512)	(1,410)
Net cash used in investing activities	(11,419)	(89,173)
Cash flows from financing activities:
Principal payments on capital leases	(1,310)	(1,346)
Issuances of common stock	108,843	73,210
Purchases of treasury stock	(234,985)	(50,257)
Net cash (used in) provided by financing activities	(127,452)	21,607
Effect of exchange rate changes on cash and cash equivalents	641	(844)
Net change in cash and cash equivalents	(81,375)	(32,182)
Cash and cash equivalents, beginning of year	775,407	701,613
Cash and cash equivalents, end of period	$ 694,032	$ 669,431

The net change during the reporting period in income tax payables net of income tax receivables.

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents.

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The net amount of deferred income taxes and income tax credits less the tax benefit from exercise of stock options.

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The effect of exchange rate changes on cash balances held in foreign currencies.

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The net realized gain or loss on investments sold during the period, which, for cash flow reporting, is a component of proceeds from investing activities.

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The net change during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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The net cash inflow (outflow) from financing activity for the period.

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The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities generally involve producing and delivering goods and providing services. Operating activity cash flows include transactions, adjustments, and changes in value that are not defined as investing or financing activities.

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The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities include all transactions and events that are not defined as investing or financing activities. Operating activities generally involve producing and delivering goods and providing services. Cash flows from operating activities are generally the cash effects of transactions and other events that enter into the determination of net income.

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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

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The cash outflow to reacquire common stock during the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow for acquisition of or capital improvements on other tangible or intangible assets not otherwise defined in the taxonomy.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash outflow for securities or other assets acquired with excess cash, having ready marketability, which qualify for treatment as an investing activity based on management's intention and intended by management to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term.

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (trading, held-to-maturity, or available-for-sale) during the period.

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The cash inflow from the issuance of an equity stock that has been previously reacquired by the entity.

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Amount of the current period expense charged against operations, the offset which is generally to the allowance for doubtful accounts for the purpose of reducing receivables, including notes receivable, to an amount that approximates their net realizable value (the amount expected to be collected).

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The cash outflow for the obligation for lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer).

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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