SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016		Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 2,348,433	$ 3,690,552		$ 2,555,902	$ 2,148,119	$ 1,999,995	$ 3,102,901	$ 2,280,397	$ 1,840,694	$ 10,743,006	$ 9,223,987	$ 8,441,971
Gross profit	2,276,361	3,589,063		2,429,818	2,019,450	1,879,383	2,947,282	2,092,906	1,672,236	10,314,692	8,591,807	7,584,130
Net income	$ 673,908	$ 506,017	[1]	$ 580,638	$ 374,424	$ 504,269	$ 1,196,732	$ 517,032	$ 333,327	$ 2,134,987	$ 2,551,360	$ 2,421,753
Net income applicable to common stockholders per basic common share	$ 13.66	$ 10.24	[1]	$ 11.71	$ 7.54	$ 10.14	$ 23.67	$ 10.02	$ 6.42	$ 43.14	$ 50.09	$ 46.30
Net income applicable to common stockholders per diluted common share	$ 13.47	10.13	[1]	$ 11.60	$ 7.47	$ 10.00	$ 23.41	$ 9.94	$ 6.36	$ 42.65	$ 49.45	$ 45.67
Impairment of goodwill										$ 940,700	$ 0	$ 0
Impairment effect on earnings per share, Basic (in dollars per share)		19.03
Impairment effect on earnings per share, Diluted (in dollars per share)		$ 18.82
OpenTable
Impairment of goodwill										$ 940,700

[1] Includes a non-cash charge in the third quarter of 2016 related to an impairment of OpenTable goodwill of $940.7 million, which is not tax deductible (see Note 9). The goodwill impairment charge reduced basic and diluted net income per share for the third quarter of 2016 by $19.03 and $18.82, respectively.