EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Numerator: Basic
Earnings from continuing operations	$ 34,305	$ 52,709
Net loss attributable to noncontrolling interests	2,394	1,872
Earnings from continuing operations attributable to IAC shareholders	36,699	54,581
Loss from discontinued operations attributable to IAC shareholders	(814)	(944)
Net earnings attributable to IAC shareholders	35,885	53,637
Numerator: Diluted
Earnings from continuing operations	34,305	52,709
Net loss attributable to noncontrolling interests	2,394	1,872
Earnings from continuing operations attributable to IAC shareholders	36,699	54,581
Loss from discontinued operations attributable to IAC shareholders	(814)	(944)
Net earnings attributable to IAC shareholders	$ 35,885	$ 53,637
Denominator: Basic
Weighted average basic shares outstanding	82,484	84,218
Denominator: Diluted
Weighted average basic shares outstanding	82,484	84,218
Dilutive securities including stock options and RSUs (in shares)	4,720	3,162
Denominator for earnings per share-weighted average shares (in shares)	87,204	87,380
Earnings (loss) per share attributable to IAC shareholders: Basic
Earnings per share from continuing operations (in dollars per share)	$ 0.44	$ 0.65
Discontinued operations (in dollars per share)	$ 0.00	$ (0.01)
Earnings per share (in dollars per share)	$ 0.44	$ 0.64
Earnings (loss) per share attributable to IAC shareholders: Diluted
Earnings per share from continuing operations (in dollars per share)	$ 0.42	$ 0.62
Discontinued operations (in dollars per share)	$ (0.01)	$ (0.01)
Earnings per share (in dollars per share)	$ 0.41	$ 0.61