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	$ 14,048	$ 17,127	$ 5,853
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	22,316	23,429	25,122
Amortization of intangible assets	12,136	2,543	2,072
Stock-based compensation, net of forfeitures	33,870	16,366	14,273
Loss/(gain) on disposal of property and equipment	(301)	(345)	346
Deferred income taxes	(5,766)	2,021	(2,903)
Tax benefit from stock-based compensation	8,391	5,973	4,965
Excess tax benefits from stock-based compensation	(8,380)	(5,967)	(3,273)
Loss/(gain) on auction rate securities Rights	0	(6,266)	2,747
Loss/(gain) on auction rate securities	0	6,266	(2,747)
Changes in operating assets and liabilities:
Accounts receivable, net	(7,205)	688	520
Inventories	766	(558)	642
Prepaid expenses and other current assets	(5,667)	(2,402)	501
Other assets	(1,402)	2	(3,282)
Accounts payable	(16,458)	8,652	1,947
Accrued and other liabilities	15,030	7,504	7,966
Deferred revenue	1,870	1,128	(859)
Net cash provided by operating activities	63,248	76,161	53,890
Cash flows from investing activities:
Acquisition of business and intangible assets, net of cash acquired	(133,705)	(5,981)	(795)
Purchases of property and equipment	(23,149)	(14,405)	(13,762)
Capitalization of software and website development costs	(10,050)	(7,405)	(3,891)
Proceeds from sale of equipment	676	2,476	0
Proceeds from the sale of auction rate securities	0	47,925	4,325
Net cash provided by (used in) investing activities	(166,228)	22,610	(14,123)
Cash flows from financing activities:
Principal payments of capital lease obligations	(6)	(9)	(91)
Proceeds from issuance of common stock upon exercise of stock options	22,277	14,703	2,740
Shares withheld for payment of employee's withholding tax liability	0	0	(1,041)
Excess tax benefits from stock-based compensation	8,380	5,967	3,273
Net cash provided by financing activities	30,651	20,661	4,881
Net increase/(decrease) in cash and cash equivalents	(72,329)	119,432	44,648
Cash and cash equivalents, beginning of period	252,244	132,812	88,164
Cash and cash equivalents, end of period	179,915	252,244	132,812
Cash paid during the period for:
Interest	0	1	12
Income taxes	140	663	2,644
Supplemental schedule of non-cash investing activities:
Net change in accrued purchases of property and equipment	412	556	2
Escrow liability from acquisition of business	$ 0	$ 0	$ 150