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

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LONG-TERM DEBT - Schedule of Long-Term Debt (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017	Dec. 04, 2017	Jun. 01, 2016
Debt Instrument [Line Items]
Less: current portion of long-term debt	$ 14,120,000	$ 13,750,000
Long-term debt, net	1,980,579,000	1,979,469,000
Match Group, Inc.
Debt Instrument [Line Items]
Long-term debt	1,275,000,000	1,275,000,000
Less: unamortized original issue discount	8,339,000	8,668,000
Less: unamortized debt issuance costs	13,219,000	13,636,000
Long-term debt, net	1,253,442,000	1,252,696,000
Match Group, Inc. \| Senior Notes \| 6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes)
Debt Instrument [Line Items]
Long-term debt	$ 400,000,000	$ 400,000,000
Stated interest rate (as a percent)	6.375%	6.375%		6.375%
Match Group, Inc. \| Senior Notes \| Match Group Senior Notes, 5.00% December 15, 2027
Debt Instrument [Line Items]
Long-term debt	$ 450,000,000	$ 450,000,000	$ 450,000,000
Stated interest rate (as a percent)	5.00%		5.00%
Match Group, Inc. \| Term Loan \| Term Loan due November 16, 2022
Debt Instrument [Line Items]
Long-term debt	$ 425,000,000	425,000,000
ANGI Homeservices
Debt Instrument [Line Items]
Less: current portion of long-term debt	13,750,000	13,750,000
Less: unamortized debt issuance costs	2,786,000	2,938,000
Long-term debt, net	255,027,000	258,312,000
ANGI Homeservices \| Term Loan \| Term Loan due November 01, 2022
Debt Instrument [Line Items]
Long-term debt	271,563,000	275,000,000
IAC/InterActiveCorp
Debt Instrument [Line Items]
Long-term debt	552,359,000	552,359,000
Less: unamortized original issue discount	63,922,000	67,158,000
Less: current portion of long-term debt	370,000	0
Less: unamortized debt issuance costs	15,957,000	16,740,000
Long-term debt, net	472,110,000	468,461,000
IAC/InterActiveCorp \| Senior Notes \| Senior Notes, 0.875% due October 1, 2022
Debt Instrument [Line Items]
Long-term debt	$ 517,500,000	517,500,000
Stated interest rate (as a percent)	0.875%
IAC/InterActiveCorp \| Senior Notes \| Senior Notes, 4.75% Due December 15, 2022
Debt Instrument [Line Items]
Long-term debt	$ 34,859,000	$ 34,859,000
Stated interest rate (as a percent)	4.75%