Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2012	Apr. 02, 2011
Cash flows from operating activities:
Net income	$ 25,692	$ 32,277
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	33,285	28,720
Stock-based compensation	26,074	20,898
Excess tax benefits from stock-based awards	(453)	(530)
Other non-cash costs, net	211	154
Changes in operating assets and liabilities:
Accounts receivable	38,698	15,899
Accounts payable and accrued expenses	(6,233)	2,089
Accrued compensation and benefits	(7,635)	(27,406)
Deferred revenue	33,482	27,169
Accrued litigation	0	(52,129)
Accrued income taxes	(11,901)	(9,198)
Other current assets and prepaid expenses	3,573	2,165
Other noncurrent assets and liabilities	(1,759)	(9,870)
Net cash provided (used) by operating activities	133,034	30,238
Cash flows from investing activities:
Additions to property and equipment	(16,624)	(11,560)
Acquisitions of businesses	(1,170)	0
Net cash used by investing activities	(17,794)	(11,560)
Cash flows from financing activities:
Borrowings under revolving credit facility	40,000	0
Repayments of borrowings under revolving credit facility	(80,000)	0
Repurchases of common stock	(14,983)	0
Proceeds from issuance of common stock	14,123	15,974
Excess tax benefits from stock-based awards	453	530
Payments of withholding taxes in connection with vesting of stock-based awards	(19,465)	(21,956)
Net cash used by financing activities	(59,872)	(5,452)
Effect of exchange rate changes on cash and cash equivalents	861	6,025
Net increase (decrease) in cash and cash equivalents	56,229	19,251
Cash and cash equivalents, beginning of period	167,878	240,253
Cash and cash equivalents, end of period	$ 224,107	$ 259,504

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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 are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).