v2.4.0.8

ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Balance at January 1 | $ (32,169,000) |  |
Net current period other comprehensive income | 22,795,000 | (19,115,000) | (38,226,000)
Balance at December 31 | (13,046,000) | (32,169,000) |
Tax provision for Other comprehensive income before reclassifications | 3,900,000 |  |
Tax provision for Amounts reclassified from accumulated other comprehensive loss | 6,900,000 |  |
Other income (expense), net | 30,309,000 | (3,012,000) | 15,490,000
Reclassification out of Accumulated Other Comprehensive Income |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Other income (expense), net |  | 2,100,000 | 2,800,000
Foreign Currency Translation Adjustment |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Balance at January 1 | (25,073,000) |  |
Other comprehensive income before reclassifications, net of tax provision of $3.9 million related to unrealized gains | 4,721,000 |  |
Amounts reclassified from accumulated other comprehensive loss, net of tax provision of $6.9 million related to unrealized gains | 0 |  |
Net current period other comprehensive income | 4,721,000 |  |
Balance at December 31 | (20,352,000) |  |
Unrealized (Losses) Gains On Available-For-Sale Securities |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Balance at January 1 | (7,096,000) |  |
Other comprehensive income before reclassifications, net of tax provision of $3.9 million related to unrealized gains | 43,235,000 |  |
Amounts reclassified from accumulated other comprehensive loss, net of tax provision of $6.9 million related to unrealized gains | (28,833,000) |  |
Net current period other comprehensive income | 14,402,000 |  |
Balance at December 31 | 7,306,000 |  |
Accumulated Other Comprehensive Loss |  |  |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] |  |  |
Balance at January 1 | (32,169,000) |  |
Other comprehensive income before reclassifications, net of tax provision of $3.9 million related to unrealized gains | 47,956,000 |  |
Amounts reclassified from accumulated other comprehensive loss, net of tax provision of $6.9 million related to unrealized gains | (28,833,000) |  |
Net current period other comprehensive income | 19,123,000 |  |
Balance at December 31 | $ (13,046,000) |  |

X
- Details
Name: | iaci_AccumulatedOtherComprehensiveIncomeLossRollForward
Namespace Prefix: | iaci_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax + References No definition available. + Details
Name: | iaci_ReclassificationfromAccumulatedOtherComprehensiveIncomeCurrentPeriodTax
Namespace Prefix: | iaci_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669686-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e681-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
Name: | us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). + 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 210.5-03.7) -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 7 -Article 5 + Details
Name: | us-gaap_NonoperatingIncomeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). + References No definition available. + Details
Name: | us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669619-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e,f) -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustments of other comprehensive income (loss). + References No definition available. + Details
Name: | us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration