SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended										12 Months Ended
	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016		Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Impairment Effects on Earnings Per Share [Line Items]
Impairment of goodwill											$ 0	$ 940,700	$ 0
Impairment Effect on Earnings Per Share, Basic							$ 19.03
Impairment Effect on Earnings Per Share, Diluted							$ 18.82
Total revenues	$ 2,803,093		$ 4,434,029	$ 3,024,556	$ 2,419,404	$ 2,348,433	$ 3,690,552		$ 2,555,902	$ 2,148,119	12,681,082	10,743,006	9,223,987
Gross profit	2,769,943		4,374,553	2,951,814	2,334,235	2,276,361	3,589,063		2,429,818	2,019,450	12,430,545	10,314,692	8,591,807
Net income	$ (555,458)	[1]	$ 1,720,391	$ 720,209	$ 455,623	$ 673,908	$ 506,017	[2]	$ 580,638	$ 374,424	$ 2,340,765	$ 2,134,987	$ 2,551,360
Net income applicable to common stockholders per basic common share	$ (11.41)	[1]	$ 35.12	$ 14.66	$ 9.26	$ 13.66	$ 10.24	[2]	$ 11.71	$ 7.54	$ 47.78	$ 43.14	$ 50.09
Net income applicable to common stockholders per diluted common share	$ (11.41)	[1]	$ 34.43	$ 14.39	$ 9.11	$ 13.47	$ 10.13	[2]	$ 11.60	$ 7.47	$ 46.86	$ 42.65	$ 49.45
Transition tax for accumulated foreign earnings, provisional income tax expense (benefit)											$ 1,600,000
Change In tax rate, deferred tax, provisional income tax expense (benefit)											$ 217,000
OpenTable
Impairment Effects on Earnings Per Share [Line Items]
Impairment of goodwill							$ 940,700					$ 940,700

[1] (1) Includes a provisional tax expense of approximately $1.6 billion related to a one-time transition tax on the mandatory deemed repatriation of accumulated unremitted international earnings and a provisional tax benefit of approximately $217 million related to the remeasurement of the Company’s U.S. deferred tax assets and liabilities, for the fourth quarter of 2017, as a result of the Tax Act (see Note 13).

[2] (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.