CONSOLIDATED FINANCIAL STATEMENT DETAILS (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Additional Consolidated Financial Statement Details [Line Items]
Other (expense) income, net	$ (7,714)	$ 15,897
IAC
Additional Consolidated Financial Statement Details [Line Items]
Other (expense) income, net	(5,805)	(9,985)
Other Income (Expense)
Additional Consolidated Financial Statement Details [Line Items]
Other-than-temporary impairment on cost method investments	3,400	2,300
Gain (loss) on mark-to-market adjustment related to a subsidiary denominated equity award issued to a non-employee	(2,700)	(1,200)
Foreign currency exchange gain (loss)	(2,600)	4,500
Interest income	$ 1,600	1,600
Gain on sale of long-term investments		1,200
Other Income (Expense) | Senior Notes | IAC
Additional Consolidated Financial Statement Details [Line Items]
Loss on redemption and repurchase of senior notes		(1,400)
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PriceRunner
Additional Consolidated Financial Statement Details [Line Items]
Disposal group, revenue			$ 7,100
Disposal group, operating income			2,200
Disposal group, adjusted EBITDA			2,600
Amortization of intangible assets			300
Depreciation			$ 100
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PriceRunner | Other Income (Expense)
Additional Consolidated Financial Statement Details [Line Items]
Gain related to sale of business		$ 13,500