Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2010
Operating activities:
Net income	$ 122,114	$ 112,635	$ 78,471
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of property and equipment	14,931	13,145	13,414
Amortization of acquired intangible assets	35,553	34,661	32,494
Amortization of debt discount and transaction costs	11,465	772	658
Stock-based compensation	61,146	48,867	32,248
Deferred income tax	(20,351)	1,266	(8,478)
Tax benefits related to employee stock option plans	24,561	8,552	30,626
Excess tax benefits from stock-based compensation	(30,311)	(41,950)	(21,510)
Other non-cash adjustments, net	1,486	476	225
Changes in assets and liabilities, net of effects of acquisitions:
Accounts receivable	(37,171)	(3,312)	(25,909)
Prepaid expenses and other assets	(1,880)	4,859	13,860
Accounts payable	(3,036)	501	3,829
Accrued liabilities and restructuring costs	(1,542)	7,015	(12,553)
Deferred revenue	60,395	20,563	11,382
Net cash provided by operating activities	237,360	208,050	148,757
Investing activities:
Purchases of short-term investments	(41,409)	(76)	(1,313)
Maturities and sales of short-term investments	7,229	1,451	183
Acquisitions, net of cash acquired	(132,209)	(63,610)	(78,573)
Purchases of property and equipment	(23,723)	(13,971)	(6,399)
Restricted cash pledged as security	(1,169)	(3,234)	(5,498)
Other investing activities, net	326	0	485
Net cash used in investing activities	(190,955)	(79,440)	(91,115)
Financing activities:
Proceeds from issuance of convertible debt, net	584,450	0	0
Proceeds from revolving credit facility	116,648	30,000	0
Principal payments on debt	(152,397)	(2,269)	(3,492)
Proceeds from issuance of common stock	33,417	80,610	86,940
Repurchases of the Company’s common stock	(220,265)	(194,059)	(204,280)
Withholding taxes related to restricted stock net share settlement	(18,212)	(17,922)	(6,140)
Excess tax benefits from stock-based compensation	30,311	41,950	21,510
Net cash provided by (used in) financing activities	373,952	(61,690)	(105,462)
Effect of foreign exchange rate changes on cash and cash equivalents	(1,196)	(2,761)	(720)
Net increase (decrease) in cash and cash equivalents	419,161	64,159	(48,540)
Cash and cash equivalents at beginning of year	308,148	243,989	292,529
Cash and cash equivalents at end of year	727,309	308,148	243,989
Supplemental disclosures:
Interest paid	10,536	2,994	3,023
Income taxes paid	$ 12,967	$ 12,883	$ 22,770