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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

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No definition available.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Revenue and Other [Line Items]
Goodwill	$ 2,572,221		$ 2,572,221		$ 2,559,066
Intangible asset	624,102		624,102		663,737
Revenue	1,104,592	$ 828,434	3,158,789	$ 2,356,654
Accounts receivable, net of allowance	$ 347,158		$ 347,158		304,027
Applications
Revenue and Other [Line Items]
Fair Value in excess of carrying amount (as a percent)	5.00%		5.00%
Goodwill	$ 460,100		$ 460,100
Intangible asset	56,600		56,600
Operating segments \| Publishing
Revenue and Other [Line Items]
Revenue	139,439	88,755	411,116	244,959
Operating segments \| Applications
Revenue and Other [Line Items]
Revenue	153,973	136,333	429,034	439,199
Operating segments \| Match Group
Revenue and Other [Line Items]
Revenue	443,943	343,418	1,272,506	951,754
Google Inc.
Revenue and Other [Line Items]
Accounts receivable, net of allowance	73,100		73,100		$ 72,400
Google Inc. \| Publishing and Applications
Revenue and Other [Line Items]
Revenue	$ 204,400	$ 176,800	$ 620,700	$ 539,200
Google Inc. \| Revenue \| Customer concentration risk
Revenue and Other [Line Items]
Concentration risk (as a percent)	19.00%	21.00%	20.00%	23.00%
Google Inc. \| Revenue \| Customer concentration risk \| Operating segments \| Publishing
Revenue and Other [Line Items]
Concentration risk (as a percent)	67.00%	72.00%	71.00%	71.00%
Google Inc. \| Revenue \| Customer concentration risk \| Operating segments \| Applications
Revenue and Other [Line Items]
Concentration risk (as a percent)	72.00%	82.00%	76.00%	83.00%
Match Group
Revenue and Other [Line Items]
Economic interest (as a percent)	80.90%		80.90%
Voting interest (as a percent)	97.50%		97.50%
ANGI Homeservices
Revenue and Other [Line Items]
Economic interest (as a percent)	86.30%		86.30%
Voting interest (as a percent)	98.40%		98.40%