Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	May 31, 2012	May 31, 2011
Cash flows from operating activities [Abstract]
Net income	$ 5,581	$ 38,481
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property and equipment	4,640	4,395
Amortization of acquired intangibles and other	12,339	12,161
Stock-based compensation	13,760	9,287
Asset impairment	848	0
Deferred income taxes	82	224
Tax benefit from stock plans	801	5,434
Excess tax benefit from stock plans	(1,171)	(4,210)
Allowances for accounts receivable	443	0
Changes in operating assets and liabilities:
Accounts receivable	23,262	32,291
Other assets	(3,891)	2,315
Accounts payable and accrued liabilities	5,614	(23,720)
Income taxes payable and uncertain tax positions	(10,844)	5,755
Deferred revenue	2,225	6,630
Net cash flows from operating activities	53,689	89,043
Cash flows from investing activities:
Purchases of investments	(25,887)	(64,525)
Sales and maturities of investments	44,855	21,827
Redemptions at par by issuers of auction rate securities	225	6,200
Purchases of property and equipment	(6,141)	(8,494)
Increase in other noncurrent assets	(52)	(888)
Net cash flows from investing activities	13,000	(45,880)
Cash flows from financing activities [Abstract]
Issuance of common stock	20,487	35,797
Withholding tax payments related to net issuance of restricted stock units	(2,452)	(1,505)
Repurchase of common stock	0	(64,899)
Excess tax benefit from stock plans	1,171	4,210
Payment of long-term debt	(286)	(190)
Net cash flows from financing activities	18,920	(26,587)
Effect of exchange rate changes on cash	(4,820)	7,307
Net increase in cash and equivalents	80,789	23,883
Cash and cash equivalents, beginning of period	161,095	286,559
Cash and cash equivalents, end of period	241,884	310,442
Supplemental disclosure [Abstract]
Cash paid for income taxes, net of refunds of $127 in 2012 and $7,796 in 2011	$ 12,558	$ 4,987