STOCK-BASED EMPLOYEE COMPENSATION (Schedule of Assumed Stock Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended	1 Months Ended	3 Months Ended	4 Months Ended	5 Months Ended
Sep. 30, 2013	Jun. 30, 2013 KAYAK [Member]	Sep. 30, 2013 KAYAK [Member]	Sep. 30, 2013 KAYAK [Member]	May 21, 2013 KAYAK [Member]
Number of Shares
Beginning balance (in shares)		540,179	208,282	540,179
Exercised (in shares)	(59,005)	(329,687)	(44,204)
Forfeited (in shares)		(2,210)	(11,023)
Ending balance (in shares)	11,996	208,282	153,055	153,055	540,179
Weighted Average Exercise Price
Beginning balance (in dollars per share)		$ 260.96	$ 343.47	$ 260.96
Exercised (in dollars per share)	$ 19.22	$ 207.93	$ 288.48
Forfeited (in dollars per share)		$ 395.99	$ 463.23
Ending balance (in dollars per share)	$ 22.67	$ 343.47	$ 350.74	$ 350.74	$ 260.96
Aggregate Intrinsic Value		$ 100,641	$ 101,048	$ 101,048	$ 314,133
Weighted Average Remaining Contractual Term		7 years 6 months		7 years 4 months	6 years 9 months
Vested and exercisable as of September 30, 2013
Number of Shares			85,583	85,583
Weighted Average Exercise Price (in dollars per share)			$ 257.74	$ 257.74
Aggregate Intrinsic Value			64,462	64,462
Weighted Average Remaining Contractual Term	1 year 4 months			6 years 8 months
Vested and exercisable as of September 30, 2013 and expected to vest thereafter, net of estimated forfeitures
Number of Shares			149,438	149,438
Weighted Average Exercise Price (in dollars per share)			$ 347.46	$ 347.46
Aggregate Intrinsic Value			$ 99,150	$ 99,150
Weighted Average Remaining Contractual Term				7 years 4 months

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