CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income	$ 30,170	$ 24,153	$ 36,883
Adjustment to net income for discontinued operation (income) loss	(1,839)	166	(16,109)
Net income from continuing operations	28,331	24,319	20,774
Adjustments to reconcile net income to net cash provided by operating activities from continuing operations:
Stock-based compensation	19,138	18,430	18,162
Excess tax benefits from stock-based compensation	(7,055)	(3,878)	(499)
Depreciation and amortization	22,632	17,610	16,692
Provision for doubtful accounts	230	188	215
Provision for (reduction of) sales return reserves	(187)	(616)	315
Loss on disposition of fixed assets	2	22	93
Non-cash impairment loss	500
Gain on investments			(2,056)
Deferred income taxes	4,700	8,423	8,129
Other	101	241	199
Changes in operating assets and liabilities, net of effect of acquisitions:
Accounts receivable	(10,198)	(5,619)	2,094
Prepaid and other assets	(6,977)	2,393	(1,906)
Accounts payable	3,734	1,997	(262)
Accrued liabilities	3,069	3,053	7,829
Deferred revenues	18,560	8,519	4,450
Income taxes payable	6,604	1,136	(1,802)
Net cash provided by operating activities from continuing operations	83,184	76,218	72,427
Cash flows from investing activities:
Cash used in acquisitions, net of cash acquired	(97,092)	(4,719)	(200)
Purchases of property and equipment	(11,252)	(17,418)	(4,575)
Capitalized software development costs	(2,358)	(2,144)	(2,893)
Proceeds from sales of investments			2,056
Purchases of marketable securities	(89,236)	(46,496)	(60,000)
Sales and maturities of marketable securities	87,428	36,496
Proceeds from disposition of fixed assets			37
Change in restricted cash			611
Net cash used in investing activities from continuing operations	(112,510)	(34,281)	(64,964)
Cash flows from financing activities:
Proceeds from exercises of stock options	7,189	14,020	8,637
Withholding taxes related to equity award net share settlement	(5,775)	(5,467)	(2,196)
Common stock repurchased and retired	(51,582)	(35,881)	(14,578)
Proceeds from common stock issued under the employee stock purchase plan	6,158	5,793	5,621
Proceeds from debt	50,000
Repayment of debt			(25,000)
Debt issuance costs	(1,901)
Excess tax benefits from stock-based compensation	7,055	3,878	499
Net cash provided by (used in) financing activities from continuing operations	11,144	(17,657)	(27,017)
Net cash transferred from (to) discontinued operation	1,655	(112)	31,959
Effect of exchange rate changes on cash and cash equivalents	104	(97)	374
Net change in cash and cash equivalents from continuing operations	(16,423)	24,071	12,779
Cash and cash equivalents of continuing operations at beginning of period	81,948	57,877	45,098
Cash and cash equivalents of continuing operations at end of period	65,525	81,948	57,877
Supplemental disclosure of cash flow information:
Cash paid for income taxes, net of refunds	2,533	1,687	2,309
Cash paid for interest	32		316
Cash flow from discontinued operation:
Net cash provided by (used in) operating activities	(1,349)	(377)	2,621
Net cash provided by investing activities	3,004		26,358
Net cash transferred from (to) continuing operations	(1,655)	112	(31,959)
Effect of exchange rates on cash and cash equivalents		(1)	(7)
Net change in cash and cash equivalents from discontinued operation		(266)	(2,987)
Cash and cash equivalents of discontinued operation at beginning of period		266	3,253
Cash and cash equivalents of discontinued operation at end of period			$ 266