Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Operating Activities
Net income	$ 59,688		$ 68,267
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	35,127	[1]	27,002	[1]
Depreciation and amortization of property and equipment	29,409		22,545
Stock-based compensation expense	43,556		30,557
Gain on investments	(85)		(3,366)
Provision for doubtful accounts	407		546
Provision for product returns	1,619		2,945
Provision for inventory reserves	331		411
Tax effect of stock-based compensation	25,643		13,856
Excess tax benefit from exercise of stock options	(26,795)		(14,597)
Deferred income tax benefit	(18,189)		2,206
Effects of exchange rate changes on monetary assets and liabilities denominated in foreign currencies	(909)		(1,202)
Other non-cash items	175		791
Total adjustments to reconcile net income to net cash provided by operating activities	90,289		81,694
Changes in operating assets and liabilities, net of the effects of acquisitions:
Accounts receivable	183,892		88,114
Inventories	(1,140)		(1,334)
Prepaid expenses and other current assets	(35,158)		(18,682)
Other assets	811		2,536
Income taxes, net	(43,333)		3,940
Accounts payable	(11,312)		(4,513)
Accrued expenses and other current liabilities	(21,338)		626
Deferred revenues	21,448		23,001
Other liabilities	5,632		(579)
Total changes in operating assets and liabilities, net of the effects of acquisitions	99,502		93,109
Net cash provided by operating activities	249,479		243,070
Investing Activities
Proceeds from sales of available-for-sale investments	(636,792)		(314,387)
Proceeds from sales of available-for-sale investments	231,782		104,185
Proceeds from maturities of available-for-sale investments	131,101		138,488
Purchases of property and equipment	(28,297)		(23,147)
Proceeds from the sales of cost method investments	0		5,559
Purchases of cost method investments	(1,102)		(1,712)
Cash paid for acquisitions, net of cash acquired	(324,049)		(24,033)
Cash paid for licensing agreements and product related intangible assets	(2,236)		(61)
Net cash used in investing activities	(629,593)		(115,108)
Financing Activities
Proceeds from issuance of common stock under stock-based compensation plans	25,251		30,260
Repayment of acquired debt	0		(2,456)
Excess tax benefit from exercise of stock options	26,795		14,597
Stock repurchases, net	(61,364)		(99,996)
Cash paid for tax withholding on vested stock awards	(2,254)		(14,102)
Net cash used in financing activities	(11,572)		(71,697)
Effect of exchange rate changes on cash and cash equivalents	(458)		1,320
Change in cash and cash equivalents	(392,144)		57,585
Cash and cash equivalents at beginning of period	643,609		333,296
Cash and cash equivalents at end of period	$ 251,465		$ 390,881

[1] Represents expenses presented to management on a consolidated basis only and not allocated to the operating segments.