Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Income Statement [Abstract]
Revenues	$ 905,089	$ 821,839	$ 2,664,043	$ 2,329,002
Cost of revenues:
Subscription	602,165	471,823	1,749,816	1,277,018
Fulfillment expenses	60,473	64,794	180,183	187,728
Total cost of revenues	662,638	536,617	1,929,999	1,464,746
Gross profit	242,451	285,222	734,044	864,256
Operating expenses:
Marketing	113,233	89,108	367,357	288,350
Technology and development	82,521	69,480	246,869	178,250
General and administrative	30,562	29,792	89,464	83,460
Total operating expenses	226,316	188,380	703,690	550,060
Operating income	16,135	96,842	30,354	314,196
Other income (expense):
Interest expense	(4,990)	(4,915)	(14,970)	(15,083)
Interest and other income (expense)	801	1,696	192	3,574
Income before income taxes	11,946	93,623	15,576	302,687
Provision for income taxes	4,271	31,163	6,321	111,780
Net income	$ 7,675	$ 62,460	$ 9,255	$ 190,907
Earnings per share:
Basic (in dollars per share)	$ 0.14	$ 1.19	$ 0.17	$ 3.63
Diluted (in dollars per share)	$ 0.13	$ 1.16	$ 0.16	$ 3.53
Weighted average common shares outstanding:
Basic (in shares)	55,541	52,569	55,508	52,599
Diluted (in shares)	58,729	53,870	58,829	54,008