EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator: Basic
Earnings from continuing operations	$ (17,995)	$ 58,540	$ 16,310	$ 111,249
Net loss attributable to noncontrolling interests	867	818	3,261	2,690
Earnings from continuing operations attributable to IAC shareholders	(17,128)	59,358	19,571	113,939
Loss from discontinued operations attributable to IAC shareholders	(868)	(1,068)	(1,682)	(2,012)
Net earnings attributable to IAC shareholders	(17,996)	58,290	17,889	111,927
Numerator: Diluted
Earnings from continuing operations	(17,995)	58,540	16,310	111,249
Net loss attributable to noncontrolling interests	867	818	3,261	2,690
Earnings from continuing operations attributable to IAC shareholders	(17,128)	59,358	19,571	113,939
Loss from discontinued operations attributable to IAC shareholders	(868)	(1,068)	(1,682)	(2,012)
Net earnings attributable to IAC shareholders	$ (17,996)	$ 58,290	$ 17,889	$ 111,927
Denominator: Basic
Weighted average basic shares outstanding	83,178	83,609	82,833	83,912
Denominator: Diluted
Weighted average basic shares outstanding	83,178	83,609	82,833	83,912
Dilutive securities including stock options and RSUs (in shares)	0	2,954	5,150	3,058
Denominator for earnings per share-weighted average shares (in shares)	83,178	86,563	87,983	86,970
Earnings (loss) per share attributable to IAC shareholders: Basic
Earnings per share from continuing operations (in dollars per share)	$ (0.21)	$ 0.71	$ 0.24	$ 1.36
Discontinued operations (in dollars per share)	$ (0.01)	$ (0.01)	$ (0.02)	$ (0.03)
Earnings per share (in dollars per share)	$ (0.22)	$ 0.70	$ 0.22	$ 1.33
Earnings (loss) per share attributable to IAC shareholders: Diluted
Earnings per share from continuing operations (in dollars per share)	$ (0.21)	$ 0.69	$ 0.22	$ 1.31
Discontinued operations (in dollars per share)	$ (0.01)	$ (0.02)	$ (0.02)	$ (0.02)
Earnings per share (in dollars per share)	$ (0.22)	$ 0.67	$ 0.20	$ 1.29