Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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LONG-TERM DEBT - Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2019	May 21, 2019	Feb. 15, 2019	Dec. 31, 2018	Dec. 04, 2017	Oct. 02, 2017	Jun. 01, 2016
Debt Instrument [Line Items]
Less: unamortized original issue discount	$ 379,324
Less: current portion of long-term debt	13,750			$ 13,750
Less: unamortized debt issuance costs	49,759
Long-term debt, net	3,138,531			2,245,548
Senior Notes \| 0.875% Exchangeable Notes due 2022
Debt Instrument [Line Items]
Stated interest rate (as a percent)						0.875%
Senior Notes \| 0.875% Exchangeable Notes due 2026
Debt Instrument [Line Items]
Stated interest rate (as a percent)		0.875%
Senior Notes \| 2.00% Exchangeable Notes due 2030
Debt Instrument [Line Items]
Stated interest rate (as a percent)		2.00%
Match Group
Debt Instrument [Line Items]
Long-term debt	1,625,000			1,535,000
Less: unamortized original issue discount	6,695			7,352
Less: unamortized debt issuance costs	15,698			11,737
Long-term debt, net	1,602,607			1,515,911
Match Group \| Term Loan \| MTCH Term Loan due November 16, 2022
Debt Instrument [Line Items]
Long-term debt	425,000			425,000
Match Group \| Credit Facility \| MTCH Credit Facility due December 7, 2023
Debt Instrument [Line Items]
Long-term debt	0			260,000
Match Group \| Senior Notes \| 6.375% MTCH Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 400,000			400,000
Stated interest rate (as a percent)	6.375%						6.375%
Match Group \| Senior Notes \| 5.00% MTCH Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 450,000			450,000
Stated interest rate (as a percent)	5.00%				5.00%
Match Group \| Senior Notes \| 5.625% MTCH Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 350,000			0
Stated interest rate (as a percent)	5.625%		5.625%
ANGI Homeservices
Debt Instrument [Line Items]
Less: current portion of long-term debt	$ 13,750			13,750
Less: unamortized debt issuance costs	2,268			2,529
Long-term debt, net	238,357			244,971
ANGI Homeservices \| Term Loan \| ANGI Term Loan due November 5, 2023
Debt Instrument [Line Items]
Long-term debt	254,375			261,250
IAC
Debt Instrument [Line Items]
Long-term debt	1,701,989			551,989
Less: unamortized original issue discount	372,629			54,025
Less: unamortized debt issuance costs	31,793			13,298
Long-term debt, net	1,297,567			484,666
IAC \| Senior Notes \| 0.875% Exchangeable Notes due 2022
Debt Instrument [Line Items]
Long-term debt	517,500			517,500
Less: unamortized original issue discount	$ 47,300			54,000
Stated interest rate (as a percent)	0.875%					0.875%
IAC \| Senior Notes \| 4.75% Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 34,489			34,489
Stated interest rate (as a percent)	4.75%
IAC \| Senior Notes \| 0.875% Exchangeable Notes due 2026
Debt Instrument [Line Items]
Long-term debt	$ 575,000			0
Less: unamortized original issue discount	$ 137,300
Stated interest rate (as a percent)	0.875%	0.875%
IAC \| Senior Notes \| 2.00% Exchangeable Notes due 2030
Debt Instrument [Line Items]
Long-term debt	$ 575,000			$ 0
Less: unamortized original issue discount	$ 188,100
Stated interest rate (as a percent)	2.00%	2.00%