Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 276,358	$ 367,515
Short-term marketable securities (note 4)	155,997	118,970
Receivable-sale of marketable securities (note 4)	40,406
Accounts receivable, net of allowance of $3,331 and $2,818 at September 30, 2013 and December 31, 2012, respectively	111,138	81,459
Receivable from Expedia, Inc., net (note 14)	33,882	23,971
Taxes receivable	10,187	24,243
Deferred income taxes, net	5,795	5,971
Prepaid expenses and other current assets	13,989	10,365
Total current assets	647,752	632,494
Long-term marketable securities (note 4)	163,525	99,248
Property and equipment, net	64,551	43,802
Deferred income taxes, net	4,218	502
Other long-term assets	16,414	13,274
Intangible assets, net (note 7)	51,007	38,190
Goodwill (note 7)	500,686	471,684
TOTAL ASSETS	1,448,153	1,299,194
Current liabilities:
Accounts payable	11,985	12,796
Deferred merchant payables (note 2)	28,596	1,303
Deferred revenue	44,087	31,563
Credit facility borrowings (note 5)	26,177	32,145
Borrowings, current (note 5)	40,000	40,000
Taxes payable	10,798	14,597
Accrued expenses and other current liabilities (note 8)	95,168	63,236
Total current liabilities	256,811	195,640
Deferred income taxes, net	10,261	11,023
Other long-term liabilities	42,275	25,563
Borrowings, net of current portion (note 5)	310,000	340,000
Total Liabilities	619,347	572,226
Commitments and Contingencies (note 9)
Stockholders' equity:
Preferred stock $0.001 par value Authorized shares: 100,000,000 Shares issued and outstanding: 0 and 0
Additional paid-in capital	590,685	531,256
Retained earnings	381,607	196,438
Accumulated other comprehensive loss	(1,308)	(869)
Treasury stock-Common stock, at cost, 2,083,709 and 0 shares, at September 30, 2013 and December 31, 2012 respectively	(142,322)
Total stockholders' equity	828,806	726,968
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	1,448,153	1,299,194
Common Stock [Member]
Stockholders' equity:
Common stock	131	130
Class B Common Stock [Member]
Stockholders' equity:
Common stock	13	13
Total stockholders' equity	$ 13	$ 13