UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Merchant revenues	$ 496,409	$ 454,804
Agency revenues	537,627	351,422
Other revenues	3,211	3,094
Total revenues	1,037,247	809,320
Cost of revenues	293,959	303,512
Gross profit	743,288	505,808
Operating expenses:
Advertising - Online	277,136	185,108
Advertising - Offline	11,157	11,614
Sales and marketing	45,537	34,778
Personnel, including stock-based compensation of $16,523 and $13,993, respectively	100,676	75,221
General and administrative	40,674	25,879
Information technology	10,735	6,670
Depreciation and amortization	15,842	12,479
Total operating expenses	501,757	351,749
Operating income	241,531	154,059
Other income (expense):
Interest income	1,098	1,421
Interest expense	(11,258)	(7,715)
Foreign currency transactions and other	(2,376)	(7,073)
Total other income (expense)	(12,536)	(13,367)
Earnings before income taxes	228,995	140,692
Income tax expense	(47,179)	(36,679)
Net income	181,816	104,013
Less: net income attributable to noncontrolling interests	(154)	(777)
Net income applicable to common stockholders	$ 181,970	$ 104,790
Net income applicable to common stockholders per basic common share (in dollars per share)	$ 3.65	$ 2.12
Weighted average number of basic common shares outstanding (in shares)	49,827	49,319
Net income applicable to common stockholders per diluted common share (in dollars per share)	$ 3.54	$ 2.05
Weighted average number of diluted common shares outstanding (in shares)	51,347	51,159