v2.4.1.9

SEGMENT INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue and long-lived assets by geography
Revenue	$ 830,754us-gaap_Revenues	$ 782,231us-gaap_Revenues	$ 756,315us-gaap_Revenues	$ 740,247us-gaap_Revenues	$ 724,455us-gaap_Revenues	$ 756,872us-gaap_Revenues	$ 799,411us-gaap_Revenues	$ 742,249us-gaap_Revenues	$ 3,109,547us-gaap_Revenues	$ 3,022,987us-gaap_Revenues	$ 2,800,933us-gaap_Revenues
Long-lived assets (excluding goodwill and intangible assets)	302,459us-gaap_PropertyPlantAndEquipmentNet				293,964us-gaap_PropertyPlantAndEquipmentNet				302,459us-gaap_PropertyPlantAndEquipmentNet	293,964us-gaap_PropertyPlantAndEquipmentNet
United States
Revenue and long-lived assets by geography
Revenue									2,146,189us-gaap_Revenues / us-gaap_StatementGeographicalAxis = country_US	2,081,485us-gaap_Revenues / us-gaap_StatementGeographicalAxis = country_US	1,966,383us-gaap_Revenues / us-gaap_StatementGeographicalAxis = country_US
Long-lived assets (excluding goodwill and intangible assets)	281,879us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US				271,916us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US				281,879us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US	271,916us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = country_US
All other countries
Revenue and long-lived assets by geography
Revenue									963,358us-gaap_Revenues / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember	941,502us-gaap_Revenues / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember	834,550us-gaap_Revenues / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember
Long-lived assets (excluding goodwill and intangible assets)	$ 20,580us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember				$ 22,048us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember				$ 20,580us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember	$ 22,048us-gaap_PropertyPlantAndEquipmentNet / us-gaap_StatementGeographicalAxis = iaci_AllOtherCountriesMember

X

- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229



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 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

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X

- 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=26872669&loc=d3e20235-122688



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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X

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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X

- Details

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Namespace Prefix:
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X

- Details

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