UNAUDITED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Agency revenues	$ 771,996	$ 569,181	$ 1,309,623	$ 920,603
Merchant revenues	551,024	530,530	1,047,433	985,334
Other revenues	3,739	3,005	6,950	6,098
Total revenues	1,326,759	1,102,716	2,364,006	1,912,035
Cost of revenues	322,617	353,489	616,576	657,001
Gross profit	1,004,142	749,227	1,747,430	1,255,034
Operating expenses:
Advertising - Online	314,480	236,282	591,616	421,391
Advertising - Offline	9,922	9,815	21,078	21,429
Sales and marketing	47,445	41,030	92,982	75,807
Personnel, including stock-based compensation of $17,612, $13,113, $34,135, and $27,106, respectively	108,030	85,766	208,706	160,988
General and administrative	39,807	29,736	80,481	55,614
Information technology	10,440	8,239	21,175	14,908
Depreciation and amortization	15,663	13,651	31,505	26,130
Total operating expenses	545,787	424,519	1,047,543	776,267
Operating income	458,355	324,708	699,887	478,767
Other income (expense):
Interest income	1,001	2,129	2,099	3,550
Interest expense	(16,882)	(7,795)	(28,141)	(15,510)
Foreign currency transactions and other	3,205	(2,451)	829	(9,523)
Total other income (expense)	(12,676)	(8,117)	(25,213)	(21,483)
Earnings before income taxes	445,679	316,591	674,674	457,284
Income tax expense	(93,025)	(60,314)	(140,204)	(96,993)
Net income	352,654	256,277	534,470	360,291
Less: net income (loss) attributable to noncontrolling interests	307	(91)	153	(867)
Net income applicable to common stockholders	$ 352,347	$ 256,368	$ 534,317	$ 361,158
Net income applicable to common stockholders per basic common share (in dollars per share)	$ 7.07	$ 5.16	$ 10.73	$ 7.29
Weighted average number of basic common shares outstanding (in shares)	49,812	49,718	49,819	49,519
Net income applicable to common stockholders per diluted common share (in dollars per share)	$ 6.88	$ 5.02	$ 10.41	$ 7.06
Weighted average number of diluted common shares outstanding (in shares)	51,226	51,105	51,306	51,134