v2.4.1.9

LONG-TERM INVESTMENTS (Details2) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2014 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Long-term investments |  |  |  |
Cost method investment, Other-than-temporary impairment | $ 63,600,000 us-gaap_CostmethodInvestmentsOtherThanTemporaryImpairment | $ 66,600,000 us-gaap_CostmethodInvestmentsOtherThanTemporaryImpairment | $ 5,000,000 us-gaap_CostmethodInvestmentsOtherThanTemporaryImpairment |
Cost Method Investment Ownership Percentage |  | 20.00%iaci_CostMethodInvestmentOwnershipPercentage |  |
Equity Method Investment, Other-than-temporary impairment |  | 4,200,000 us-gaap_EquityMethodInvestmentOtherThanTemporaryImpairment | 18,600,000 us-gaap_EquityMethodInvestmentOtherThanTemporaryImpairment |
Long-term marketable equity securities |  |  |  |
Gross unrealized loss |  | 1,387,000 us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax | 4,784,000 us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax |
Other than temporary impairment losses |  |  |  | 8,700,000 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities
Other than temporary impairment recognized in earnings |  | 66,601,000 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities | 5,268,000 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities | 8,685,000 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities
Period in unrealized loss position |  |  |  | 1 year
Percentage fair value less than cost |  |  |  | 50.00%iaci_OtherThanTemporaryImpairmentLossesMeasurementPercentageFairValueLessThanCost
Marketable equity security |  |  |  |
Long-term marketable equity securities |  |  |  |
Cost basis |  | 8,700,000 us-gaap_AvailableForSaleEquitySecuritiesAmortizedCostBasis / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember | 8,800,000 us-gaap_AvailableForSaleEquitySecuritiesAmortizedCostBasis / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |
Gross unrealized loss |  | $ 1,200,000 us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember | $ 3,000,000 us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the cost method of accounting. + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The percentage that the fair value of a long-term investment was of its cost basis before the Company recorded an other than temporary impairment charge. + References No definition available. + Details
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- Definition The time period in which the long-term investment was in an unrealized loss position before the Company recorded an other than temporary impairment charge. + References No definition available. + Details
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596 + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=35687916&loc=d3e32787-111569 + Details
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- Definition The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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