GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Statement of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	$ 152,008	$ 67,863
Cash flows from investing activities:
Acquisitions, net of cash acquired	(21,295)	(52,365)
Capital expenditures	(14,801)	(11,157)
Proceeds from maturities and sales of marketable debt securities	5,000	75,350
Purchases of marketable debt securities	(4,975)	(19,926)
Purchases of investments	(18,180)	(29)
Net cash (used in) provided by investing activities	15	97,496
Intercompany		0
Other, net	9,347	213
Net cash (used in) provided by investing activities	(44,889)	89,582
Cash flows from financing activities:
Purchase of noncontrolling interests	(234)	(12,259)
Acquisition-related contingent consideration payments	(185)	(3,860)
Intercompany	0	0
Other, net	2,476	250
Net cash used in financing activities	(83,150)	(119,180)
Total cash provided	23,969	38,265
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	2,746	4,002
Net increase in cash, cash equivalents, and restricted cash	26,715	42,267
Cash, cash equivalents, and restricted cash at beginning of period	1,633,682	1,360,199
Cash, cash equivalents, and restricted cash at end of period	1,660,397	1,402,466
IAC
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	1,562	(18,973)
Cash flows from investing activities:
Acquisitions, net of cash acquired	(4,134)	0
Capital expenditures	0	(87)
Proceeds from maturities and sales of marketable debt securities	5,000	75,350
Purchases of marketable debt securities	(4,975)	(19,926)
Purchases of investments	(18,180)	0
Net cash (used in) provided by investing activities	0	0
Intercompany		(10,671)
Other, net	(5,000)	0
Net cash (used in) provided by investing activities	(27,289)	44,666
Cash flows from financing activities:
Purchase of noncontrolling interests	0	0
Acquisition-related contingent consideration payments	0	0
Intercompany	308,822	17,585
Other, net	2,674	251
Net cash used in financing activities	335,468	(90,505)
Total cash provided	309,741	(64,812)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	26	10
Net increase in cash, cash equivalents, and restricted cash	309,767	(64,802)
Cash, cash equivalents, and restricted cash at beginning of period	585,639	573,784
Cash, cash equivalents, and restricted cash at end of period	895,406	508,982
Guarantor Subsidiaries
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	319,686	18,406
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	0
Capital expenditures	(570)	(852)
Proceeds from maturities and sales of marketable debt securities	0	0
Purchases of marketable debt securities	0	0
Purchases of investments	0	0
Net cash (used in) provided by investing activities	0	0
Intercompany		0
Other, net	3,884	31
Net cash (used in) provided by investing activities	3,314	(821)
Cash flows from financing activities:
Purchase of noncontrolling interests	0	0
Acquisition-related contingent consideration payments	0	0
Intercompany	(323,000)	(17,585)
Net cash used in financing activities	(323,000)	(17,585)
Net increase in cash, cash equivalents, and restricted cash	0	0
Cash, cash equivalents, and restricted cash at end of period	0	0
Non-Guarantor Subsidiaries
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	107,605	68,430
Cash flows from investing activities:
Acquisitions, net of cash acquired	(17,161)	(52,365)
Capital expenditures	(14,231)	(10,218)
Proceeds from maturities and sales of marketable debt securities	0	0
Purchases of marketable debt securities	0	0
Purchases of investments	0	(29)
Net cash (used in) provided by investing activities	15	97,496
Intercompany		0
Other, net	10,463	182
Net cash (used in) provided by investing activities	(20,914)	35,066
Cash flows from financing activities:
Purchase of noncontrolling interests	(234)	(12,259)
Acquisition-related contingent consideration payments	(185)	(3,860)
Intercompany	(262,667)	10,671
Other, net	(198)	(1)
Net cash used in financing activities	(372,463)	(419)
Total cash provided	(285,772)	103,077
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	2,720	3,992
Net increase in cash, cash equivalents, and restricted cash	(283,052)	107,069
Cash, cash equivalents, and restricted cash at beginning of period	1,048,043	786,415
Cash, cash equivalents, and restricted cash at end of period	764,991	893,484
Eliminations
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	(276,845)	0
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	0
Capital expenditures	0	0
Proceeds from maturities and sales of marketable debt securities	0	0
Purchases of marketable debt securities	0	0
Purchases of investments	0	0
Net cash (used in) provided by investing activities	0	0
Intercompany		10,671
Other, net	0	0
Net cash (used in) provided by investing activities	0	10,671
Cash flows from financing activities:
Purchase of noncontrolling interests	0	0
Acquisition-related contingent consideration payments	0	0
Intercompany	276,845	(10,671)
Net cash used in financing activities	276,845	(10,671)
Net increase in cash, cash equivalents, and restricted cash	0	0
Cash, cash equivalents, and restricted cash at end of period	0	0
ANGI Homeservices
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt	(3,438)	0
ANGI Homeservices \| IAC
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt	0
ANGI Homeservices \| Guarantor Subsidiaries
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt	0
ANGI Homeservices \| Non-Guarantor Subsidiaries
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt	(3,438)
ANGI Homeservices \| Eliminations
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt	0
IAC/InterActiveCorp
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt	0	(26,590)
Purchase of treasury stock		(56,424)
Proceeds from the exercise of stock options	24,254	13,252
Withholding taxes paid on behalf of employees on net settled stock-based awards	(282)	(38,579)
IAC/InterActiveCorp \| IAC
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt		(26,590)
Purchase of treasury stock		(56,424)
Proceeds from the exercise of stock options	24,254	13,252
Withholding taxes paid on behalf of employees on net settled stock-based awards	(282)	(38,579)
IAC/InterActiveCorp \| Guarantor Subsidiaries
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt		0
Proceeds from the exercise of stock options	0	0
Withholding taxes paid on behalf of employees on net settled stock-based awards	0	0
IAC/InterActiveCorp \| Non-Guarantor Subsidiaries
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt		0
Proceeds from the exercise of stock options	0	0
Withholding taxes paid on behalf of employees on net settled stock-based awards	0	0
IAC/InterActiveCorp \| Eliminations
Cash flows from financing activities:
Principal payment on ANGI Homeservices debt		0
Proceeds from the exercise of stock options	0	0
Withholding taxes paid on behalf of employees on net settled stock-based awards	0	0
Match Group
Cash flows from financing activities:
Purchase of treasury stock	(32,465)	0
Match Group \| Non-Guarantor Subsidiaries
Cash flows from financing activities:
Purchase of treasury stock	(32,465)
Match Group and ANGI Homeservices
Cash flows from financing activities:
Proceeds from the exercise of stock options	1,752	7,111
Withholding taxes paid on behalf of employees on net settled stock-based awards	(75,028)	(2,081)
Match Group and ANGI Homeservices \| IAC
Cash flows from financing activities:
Proceeds from the exercise of stock options	0	0
Withholding taxes paid on behalf of employees on net settled stock-based awards	0	0
Match Group and ANGI Homeservices \| Guarantor Subsidiaries
Cash flows from financing activities:
Proceeds from the exercise of stock options	0	0
Withholding taxes paid on behalf of employees on net settled stock-based awards	0	0
Match Group and ANGI Homeservices \| Non-Guarantor Subsidiaries
Cash flows from financing activities:
Proceeds from the exercise of stock options	1,752	7,111
Withholding taxes paid on behalf of employees on net settled stock-based awards	(75,028)	(2,081)
Match Group and ANGI Homeservices \| Eliminations
Cash flows from financing activities:
Proceeds from the exercise of stock options	0	0
Withholding taxes paid on behalf of employees on net settled stock-based awards	$ 0	$ 0

Business combination contingent consideration cash payment financing.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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