Represents the period over which deferred revenue is recognized.

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

+ Details

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - REVENUE AND CONCENTRATION RISK (Details) - USD ($) $ 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
Certain Risks and Concentrations
Revenue	$ 811,162	$ 764,102	$ 745,439	$ 819,179	$ 848,728	$ 838,561	$ 771,132	$ 772,512	$ 3,139,882	$ 3,230,933	$ 3,109,547
Accounts receivable, net	220,138				250,077				220,138	250,077
Google Inc.
Certain Risks and Concentrations
Accounts receivable, net	65,800				97,200				$ 65,800	$ 97,200
Google Inc. \| Revenue \| Customer Concentration Risk
Certain Risks and Concentrations
Concentration risk (percentage)									26.00%	40.00%	45.00%
Publishing and Applications \| Google Inc.
Certain Risks and Concentrations
Revenue									$ 824,400	$ 1,300,000	$ 1,400,000
Operating Segments \| Match Group
Certain Risks and Concentrations
Revenue									$ 1,222,526	1,020,431	888,268
Operating Segments \| Match Group \| Minimum
Deferred revenue
Revenue recognition period									1 month
Operating Segments \| Match Group \| Maximum
Deferred revenue
Revenue recognition period									6 months
Operating Segments \| Match Group \| Dating
Deferred revenue
Deferred revenue	161,100				144,400				$ 161,100	144,400
Operating Segments \| Match Group \| Non-dating
Deferred revenue
Deferred revenue	23,300				25,700				23,300	25,700
Operating Segments \| HomeAdvisor
Deferred revenue
Deferred revenue	18,800				11,900				18,800	11,900
Certain Risks and Concentrations
Revenue									$ 498,890	361,201	283,541
Operating Segments \| HomeAdvisor \| Subscription term, one month
Deferred revenue
Revenue recognition period									1 month
Operating Segments \| HomeAdvisor \| Subscription term, three months
Deferred revenue
Revenue recognition period									3 months
Operating Segments \| HomeAdvisor \| Subscription term, one year
Deferred revenue
Revenue recognition period									1 year
Operating Segments \| Video
Certain Risks and Concentrations
Revenue									$ 228,649	213,317	182,454
Operating Segments \| Video \| Minimum
Deferred revenue
Revenue recognition period									1 month
Operating Segments \| Video \| Maximum
Deferred revenue
Revenue recognition period									1 year
Operating Segments \| Video \| Vimeo
Deferred revenue
Deferred revenue	36,700				30,400				$ 36,700	30,400
Operating Segments \| Video \| Electus
Deferred revenue
Deferred revenue	23,100				24,400				23,100	24,400
Operating Segments \| Publishing
Certain Risks and Concentrations
Revenue									$ 407,313	$ 691,686	$ 791,549
Operating Segments \| Publishing \| Google Inc. \| Revenue \| Customer Concentration Risk
Certain Risks and Concentrations
Concentration risk (percentage)									73.00%	83.00%	83.00%
Operating Segments \| Applications
Deferred revenue
Deferred revenue	$ 26,100				$ 21,000				$ 26,100	$ 21,000
Certain Risks and Concentrations
Revenue									$ 604,140	$ 760,748	$ 776,707
Operating Segments \| Applications \| Google Inc. \| Revenue \| Customer Concentration Risk
Certain Risks and Concentrations
Concentration risk (percentage)									87.00%	94.00%	97.00%
Operating Segments \| Applications \| Minimum
Deferred revenue
Revenue recognition period									1 year
Operating Segments \| Applications \| Maximum
Deferred revenue
Revenue recognition period									2 years