CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net earnings	$ 409,230us-gaap_ProfitLoss	$ 283,725us-gaap_ProfitLoss	$ 160,796us-gaap_ProfitLoss
Other comprehensive (loss) income, net of tax:
Change in foreign currency translation adjustment	(66,874)	7,353	712
Change in unrealized gains and losses of available-for-sale securities (net of tax benefits of $1,852, $3,050 and $3,981 in 2014, 2013 and 2012, respectively)	(8,591)	15,442	(19,827)
Total other comprehensive (loss) income	(75,465)	22,795	(19,115)
Comprehensive income	333,765	306,520	141,681
Comprehensive loss (income) attributable to noncontrolling interests	6,454	(1,613)	(2,141)
Comprehensive income attributable to IAC shareholders	$ 340,219us-gaap_ComprehensiveIncomeNetOfTax	$ 304,907us-gaap_ComprehensiveIncomeNetOfTax	$ 139,540us-gaap_ComprehensiveIncomeNetOfTax

The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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