INCOME TAXES (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2009
Income Tax Disclosure [Abstract]
Income tax provision (benefit)	$ 27,606,000	$ (32,003,000)	$ 83,360,000	$ (6,444,000)
Pretax income	73,791,000	35,970,000	208,799,000	127,327,000
Deferred tax liability in connection with the acquisition		43,600,000		43,600,000
Match's equity method investment in Meetic (as a percent)						27.00%
Effective tax rate (as a percent)	37.00%		40.00%
Federal statutory rate (as a percent)	35.00%		35.00%	35.00%
Total unrecognized tax benefits including interest	485,800,000		485,800,000		462,800,000
Unrecognized tax benefits, including interest, increased due to a net increase in deductible timing differences			23,000,000
Portion of unrecognized tax benefits included in income taxes payable	468,500,000		468,500,000
Portion of unrecognized tax benefits related to deferred tax assets included in deferred income taxes	12,100,000		12,100,000
Portion of unrecognized tax benefits included in accrued expenses and other current liabilities	5,200,000		5,200,000
Unrecognized tax benefits, tax positions for which the ultimate deductibility is highly certain but timing is uncertain	79,800,000		79,800,000
Unrecognized tax benefit, if recognized would reduce income tax expense for continuing operations	94,700,000		94,700,000
Unrecognized tax benefit, if recognized would reduce income tax expense for discontinued operations	226,400,000		226,400,000
Interest expense related to unrecognized tax benefits from continuing operations	1,600,000		3,300,000
Interest benefit related to unrecognized tax benefits from discontinued operations	400,000		3,800,000
Accrued interest on unrecognized tax benefits	112,200,000		112,200,000		111,200,000
Accrued penalties on unrecognized tax benefits	2,800,000		2,800,000		2,500,000
Reasonably possible decrease in unrecognized tax benefits within next twelve months	68,900,000		68,900,000
Reasonably possible decrease in income tax provision within next twelve months	$ 13,300,000		$ 13,300,000