v2.4.1.9

SUPPLEMENTAL CASH FLOW INFORMATION (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental Cash Flow Information [Abstract]
Fair Value Of Contingent Consideration At Date Of Acquisition	$ 8,800,000iaci_FairValueOfContingentConsiderationAtDateOfAcquisition	$ 41,400,000iaci_FairValueOfContingentConsiderationAtDateOfAcquisition
Cash paid (received) during the year for:
Interest	54,027,000us-gaap_InterestPaidNet	28,705,000us-gaap_InterestPaidNet	5,214,000us-gaap_InterestPaidNet
Income tax payments	63,521,000us-gaap_IncomeTaxesPaid	112,087,000us-gaap_IncomeTaxesPaid	43,316,000us-gaap_IncomeTaxesPaid
Income tax refunds	$ (10,477,000)us-gaap_ProceedsFromIncomeTaxRefunds	$ (17,683,000)us-gaap_ProceedsFromIncomeTaxRefunds	$ (8,187,000)us-gaap_ProceedsFromIncomeTaxRefunds

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- Definition

Fair Value Of Contingent Consideration At Date Of Acquisition

+ References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

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- Definition

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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- Definition

The amount of cash received during the period as refunds for the overpayment of taxes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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