Goodwill Deductions During Period

No definition available.

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- Definition

Number of Operating Segments after Split

+ References

No definition available.

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- Definition

Number of Reportable Segments after Split

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

+ Details

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 350
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

+ Details

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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GOODWILL AND INTANGIBLE ASSETS - SCHEDULE OF GOODWILL BY REPORTING UNIT (Details) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($) segment	Sep. 30, 2015 USD ($) segment	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Goodwill
Balance at beginning of period		$ 1,754,926	$ 2,245,364	$ 1,754,926
Additions			32,237	556,575
(Deductions)			(67,811)	(3,711)
Impairment			(275,367)	(14,056)	$ 0
Foreign Exchange Translation			(10,371)	(48,370)
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				0
Balance at end of period	$ 2,245,364		$ 1,924,052	2,245,364	1,754,926
Number of reportable segments \| segment			6
Search & Applications
Goodwill
Balance at beginning of period		$ 774,822	$ 0	774,822
Additions				1,450
(Deductions)				0
Impairment				0
Foreign Exchange Translation				(1,230)
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				(775,042)
Balance at end of period	$ 0			0	774,822
Number of operating segments \| segment		1
Number of reportable segments \| segment		1
Number of operating segments after split \| segment	3
Number of reportable segments after split \| segment	3
Match Group
Goodwill
Balance at beginning of period		$ 715,733	1,218,607	715,733
Additions			603	549,146
(Deductions)			(2,983)	0
Impairment			0	0
Foreign Exchange Translation			(9,689)	(46,272)
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				0
Balance at end of period	$ 1,218,607		1,206,538	1,218,607	715,733
HomeAdvisor
Goodwill
Balance at beginning of period		151,321	150,251	151,321
Additions			21,985	0
(Deductions)			0	0
Impairment			0	0
Foreign Exchange Translation			(1,625)	(1,070)
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				0
Balance at end of period	150,251		170,611	150,251	151,321
Video
Goodwill
Balance at beginning of period		15,590	15,590	15,590
Additions			9,649	0
(Deductions)			0	0
Impairment			0	0
Foreign Exchange Translation			0	0
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				0
Balance at end of period	15,590		25,239	15,590	15,590
Video \| Connected Ventures
Goodwill
Accumulated goodwill impairment loss	11,600		11,600	11,600
Applications
Goodwill
Balance at beginning of period		0	447,242	0
Additions			0	0
(Deductions)			0	0
Impairment			0	0
Foreign Exchange Translation			0	0
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				447,242
Balance at end of period	447,242		447,242	447,242	0
Accumulated goodwill impairment loss	529,100		529,100	529,100
Publishing
Goodwill
Balance at beginning of period		0	277,192	0
Additions			0	3,504
(Deductions)			(1,968)	0
Impairment			(275,367)	0
Foreign Exchange Translation			143	963
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				272,725
Balance at end of period	277,192		0	277,192	0
Accumulated goodwill impairment loss	322,600		598,000	322,600
Other
Goodwill
Balance at beginning of period		$ 97,460	136,482	97,460
Additions			0	2,475
(Deductions)			(62,860)	(3,711)
Impairment			0	(14,056)
Foreign Exchange Translation			800	(761)
Allocation of IAC's former Search & Applications Segment Goodwill Based on Relative Fair Value				55,075
Balance at end of period	136,482		$ 74,422	136,482	$ 97,460
Other \| PriceRunner
Goodwill
Accumulated goodwill impairment loss	65,200			65,200
Other \| ShoeBuy
Goodwill
Accumulated goodwill impairment loss	$ 42,100			$ 42,100