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- Definition

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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- Definition

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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- 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

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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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		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Revenue and Other [Line Items]
Retained earnings	$ 921,268		$ 921,268			$ 595,038
Revenue	1,059,122	$ 767,387	2,054,197	$ 1,528,220
Accounts receivable, net of allowance	343,576		343,576			304,027
Operating segments \| Publishing
Revenue and Other [Line Items]
Revenue	137,355	78,124	271,677	156,204
Operating segments \| Applications
Revenue and Other [Line Items]
Revenue	143,074	143,969	275,061	302,866
Operating segments \| Match Group
Revenue and Other [Line Items]
Revenue	421,196	309,572	828,563	608,336
Google Inc.
Revenue and Other [Line Items]
Accounts receivable, net of allowance	73,400		73,400			72,400
Google Inc. \| Publishing and Applications
Revenue and Other [Line Items]
Revenue	$ 204,900	$ 174,600	$ 416,200	$ 362,400
Google Inc. \| Revenue \| Customer concentration risk
Revenue and Other [Line Items]
Concentration risk (as a percent)	19.00%	23.00%	20.00%	24.00%
Google Inc. \| Revenue \| Customer concentration risk \| Operating segments \| Publishing
Revenue and Other [Line Items]
Concentration risk (as a percent)	71.00%	70.00%	73.00%	70.00%
Google Inc. \| Revenue \| Customer concentration risk \| Operating segments \| Applications
Revenue and Other [Line Items]
Concentration risk (as a percent)	75.00%	83.00%	79.00%	83.00%
Match Group, Inc.
Revenue and Other [Line Items]
Economic interest (as a percent)	81.20%		81.20%
Voting interest (as a percent)	97.60%		97.60%
ANGI Homeservices
Revenue and Other [Line Items]
Economic interest (as a percent)	86.40%		86.40%
Voting interest (as a percent)	98.50%		98.50%
Accounting Standards Update 2014-09
Revenue and Other [Line Items]
Retained earnings					$ 40,200	$ 3,400
Accounting Standards Update 2014-09 \| Applications
Revenue and Other [Line Items]
Retained earnings					$ 15,500