Match (MTCH) 10-Q 9 Nov 17 2017 Q3 Quarterly report Financial data

DOCUMENT AND ENTITY INFORMATION

DOCUMENT AND ENTITY INFORMATION - shares	9 Months Ended
	Sep. 30, 2017	Nov. 03, 2017
Entity Registrant Name	IAC/INTERACTIVECORP
Entity Central Index Key	891,103
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Stock
Entity Common Stock, Shares Outstanding		76,195,855
Class B Convertible Common Stock
Entity Common Stock, Shares Outstanding		5,789,499

CONSOLIDATED BALANCE SHEET (Una

CONSOLIDATED BALANCE SHEET (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
ASSETS
Cash and cash equivalents	$ 1,255,317	$ 1,329,187
Marketable securities	0	89,342
Accounts receivable, net of allowance of $12,847 and $16,405, respectively	271,209	220,138
Other current assets	200,377	204,068
Total current assets	1,726,903	1,842,735
Property and equipment, net of accumulated depreciation and amortization of $314,703 at September 30, 2017 and $311,834 at December 31, 2016	320,277	306,248
Goodwill	2,501,589	1,924,052
Intangible assets, net	660,103	355,451
Long-term investments	120,806	122,810
Deferred income taxes	129,879	2,511
Other non-current assets	81,398	92,066
TOTAL ASSETS	5,540,955	4,645,873
LIABILITIES:
Current portion of long-term debt	0	20,000
Accounts payable	104,806	62,863
Deferred revenue	343,413	285,615
Accrued expenses and other current liabilities	387,307	344,910
Total current liabilities	835,526	713,388
Long-term debt, net of current portion	1,649,267	1,582,484
Income taxes payable	33,290	33,528
Deferred income taxes	36,023	228,798
Other long-term liabilities	37,165	44,178
Redeemable noncontrolling interests	40,981	32,827
Commitments and contingencies
SHAREHOLDERS' EQUITY:
Additional paid-in capital	12,192,645	11,921,559
Retained earnings	562,234	290,114
Accumulated other comprehensive loss	(99,513)	(166,123)
Treasury stock 194,163 and 193,445 shares, respectively	(10,226,721)	(10,176,600)
Total IAC shareholders' equity	2,428,921	1,869,222
Noncontrolling interests	479,782	141,448
Total shareholders' equity	2,908,703	2,010,670
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	5,540,955	4,645,873
Common Stock
SHAREHOLDERS' EQUITY:
Common stock	260	256
Class B Convertible Common Stock
SHAREHOLDERS' EQUITY:
Common stock	$ 16	$ 16

CONSOLIDATED BALANCE SHEET (Un3

CONSOLIDATED BALANCE SHEET (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Allowance for accounts receivable	$ 12,847	$ 16,405
Accumulated depreciation and amortization, property and equipment	$ 314,703	$ 311,834
Treasury stock, shares (in shares)	194,163,000	193,445,000
Common Stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized shares (in shares)	1,600,000,000	1,600,000,000
Common stock, issued shares (in shares)	259,875,000	255,672,000
Common stock, outstanding shares (in shares)	76,080,000	72,595,000
Class B Convertible Common Stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized shares (in shares)	400,000,000	400,000,000
Common stock, issued shares (in shares)	16,157,000	16,157,000
Common stock, outstanding shares (in shares)	5,789,000	5,789,000

CONSOLIDATED STATEMENT OF OPERA

CONSOLIDATED STATEMENT OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue	$ 828,434	$ 764,102	$ 2,356,654	$ 2,328,720
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	166,290	179,131	451,281	543,262
Selling and marketing expense	352,879	292,996	1,023,394	972,490
General and administrative expense	235,580	124,469	529,397	404,296
Product development expense	70,645	49,704	180,835	162,367
Depreciation	17,263	17,951	55,490	51,321
Amortization of intangibles	4,366	14,267	22,151	65,062
Goodwill impairment	0	0	0	275,367
Total operating costs and expenses	847,023	678,518	2,262,548	2,474,165
Operating (loss) income	(18,589)	85,584	94,106	(145,445)
Interest expense	(25,036)	(27,118)	(74,556)	(82,622)
Other (expense) income, net	(10,216)	11,700	(7,700)	20,405
(Loss) earnings before income taxes	(53,841)	70,166	11,850	(207,662)
Income tax benefit (provision)	279,480	(17,826)	322,809	77,394
Net earnings (loss)	225,639	52,340	334,659	(130,268)
Net earnings attributable to noncontrolling interests	(45,996)	(9,178)	(62,539)	(13,063)
Net earnings (loss) attributable to IAC shareholders	$ 179,643	$ 43,162	$ 272,120	$ (143,331)
Per share information attributable to IAC shareholders:
Basic earnings (loss) per share (in dollars per share)	$ 2.22	$ 0.54	$ 3.43	$ (1.78)
Diluted earnings (loss) per share (in dollars per share)	$ 1.79	$ 0.49	$ 2.82	$ (1.78)
Stock-based compensation expense by function:
Stock-based compensation expense	$ 134,472	$ 23,661	$ 207,362	$ 82,610
Cost of revenue
Stock-based compensation expense by function:
Stock-based compensation expense	414	597	1,389	1,904
Selling and marketing expense
Stock-based compensation expense by function:
Stock-based compensation expense	20,970	1,465	24,420	5,026
General and administrative expense
Stock-based compensation expense by function:
Stock-based compensation expense	94,432	18,248	153,123	59,957
Product development expense
Stock-based compensation expense by function:
Stock-based compensation expense	$ 18,656	$ 3,351	$ 28,430	$ 15,723

CONSOLIDATED STATEMENT OF COMPR

CONSOLIDATED STATEMENT OF COMPREHENSIVE OPERATIONS (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings (loss)		$ 225,639	$ 52,340	$ 334,659	$ (130,268)
Other comprehensive income (loss), net of tax:
Change in foreign currency translation adjustment	[1]	44,126	(4,808)	84,824	7,596
Change in unrealized gains and losses of available-for-sale securities (net of tax benefit)	[2]	0	(145)	(4,026)	1,510
Total other comprehensive income (loss), net of tax		44,126	(4,953)	80,798	9,106
Comprehensive income (loss)		269,765	47,387	415,457	(121,162)
Comprehensive income attributable to noncontrolling interests		(52,897)	(9,502)	(76,727)	(13,881)
Comprehensive income (loss) attributable to IAC shareholders		$ 216,868	$ 37,885	$ 338,730	$ (135,043)
[1]	The nine months ended September 30, 2017 and 2016 include amounts reclassified out of other comprehensive income into earnings. See Note 7—Accumulated Other Comprehensive Loss for additional information.
[2]	The nine months ended September 30, 2017 and three and nine months ended September 30, 2016 include unrealized gains reclassified out of other comprehensive income into earnings. See Note 7—Accumulated Other Comprehensive Loss for additional information.

CONSOLIDATED STATEMENT OF COMP6

CONSOLIDATED STATEMENT OF COMPREHENSIVE OPERATIONS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Tax benefit related to change in unrealized gains and losses of available-for-sale securities	$ 85	$ 3,846	$ 868

CONSOLIDATED STATEMENT OF SHARE

CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (Unaudited) - 9 months ended Sep. 30, 2017 - USD ($) shares in Thousands, $ in Thousands	Total	Redeemable Noncontrolling Interests	Total IAC Shareholders' Equity	Common StockCommon Stock	Common StockClass B Convertible Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Treasury Stock	Noncontrolling Interests
Beginning balance at Dec. 31, 2016	$ 2,010,670		$ 1,869,222	$ 256	$ 16	$ 11,921,559	$ 290,114	$ (166,123)	$ (10,176,600)	$ 141,448
Beginning balance, common stock (in shares) at Dec. 31, 2016				255,672	16,157
Increase (Decrease) in Shareholders' Equity
Net earnings	330,802		272,120				272,120			58,682
Other comprehensive income, net of tax	79,967		66,610					66,610		13,357
Stock-based compensation expense	189,570		53,491			53,491				136,079
Issuance of common stock pursuant to stock-based awards, net of withholding taxes	11,885		11,885	$ 4		11,881
Issuance of common stock pursuant to stock-based awards, net of withholding taxes (in shares)				4,203
Purchase of treasury stock	(50,121)		(50,121)						(50,121)
Purchase of noncontrolling interests	(633)									(633)
Adjustment of redeemable noncontrolling interests to fair value	(2,977)		(2,977)			(2,977)
Issuance of Match Group common stock pursuant to stock-based awards, net of withholding taxes, and impact to noncontrolling interests in Match Group	(440,801)		(436,831)			(436,831)				(3,970)
Acquisition of Angie's List and creation of noncontrolling interests in ANGI Homeservices	779,471		645,475			645,475				133,996
Other	870		47			47				823
Ending balance at Sep. 30, 2017	2,908,703		$ 2,428,921	$ 260	$ 16	$ 12,192,645	$ 562,234	$ (99,513)	$ (10,226,721)	$ 479,782
Ending balance, common stock (in shares) at Sep. 30, 2017				259,875	16,157
Beginning balance at Dec. 31, 2016	32,827	$ 32,827
Increase (Decrease) in Redeemable Noncontrolling Interests
Net earnings		3,857
Other comprehensive income, net of tax		831
Stock-based compensation expense		1,577
Purchase of redeemable noncontrolling interests		(12,428)
Adjustment of redeemable noncontrolling interests to fair value		2,977
Noncontrolling interests created in acquisitions		17,692
Other		(6,352)
Ending balance at Sep. 30, 2017	$ 40,981	$ 40,981

CONSOLIDATED STATEMENT OF CASH

CONSOLIDATED STATEMENT OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities:
Net earnings (loss)	$ 334,659	$ (130,268)
Adjustments to reconcile net earnings (loss) to net cash provided by operating activities:
Stock-based compensation expense	207,362	82,610
Depreciation	55,490	51,321
Amortization of intangibles	22,151	65,062
Goodwill impairment	0	(275,367)
Deferred income taxes	(344,120)	(99,955)
Acquisition-related contingent consideration fair value adjustments	4,945	7,993
Gain from the sale of businesses and investments, net	(24,031)	(13,416)
Impairment of long-term investments	7,746	4,894
Acquisition-related contingent consideration payment	(11,140)	0
Bad debt expense	20,935	12,493
Other adjustments, net	22,975	(5,619)
Changes in assets and liabilities, net of effects of acquisitions and dispositions:
Accounts receivable	(78,612)	32,950
Other assets	(17,534)	(19,775)
Accounts payable and other current liabilities	47,547	(63,669)
Income taxes payable and receivable	4,433	(37,081)
Deferred revenue	44,791	31,352
Net cash provided by operating activities	297,597	194,259
Cash flows from investing activities:
Acquisitions, net of cash acquired	(69,113)	(2,524)
Capital expenditures	(56,519)	(62,739)
Investments in time deposits	0	(87,500)
Proceeds from maturities of time deposits	0	87,500
Proceeds from maturities and sales of marketable debt securities	114,350	79,210
Purchases of marketable debt securities	(24,909)	(229,246)
Purchases of investments	(9,105)	(7,211)
Net proceeds from the sale of businesses and investments	125,220	110,536
Other, net	1,319	5,562
Net cash provided by (used in) investing activities	81,243	(106,412)
Cash flows from financing activities:
Purchase of IAC treasury stock	(56,424)	(247,256)
Proceeds from Match Group 6.375% Senior Notes offering	0	400,000
Proceeds from Match Group Term Loan	75,000	0
Principal payment on Match Group Term Loan	0	(410,000)
Debt issuance costs	(2,637)	(5,048)
Repurchases of IAC Senior Notes	(31,590)	(126,271)
Proceeds from the exercise of IAC stock options	69,065	19,536
Withholding taxes paid on behalf of IAC net settled stock-based awards	(57,180)	(26,684)
Proceeds from the exercise of Match Group stock options	57,705	30,246
Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards	(501,437)	(29,779)
Purchase of noncontrolling interests	(13,011)	(2,529)
Acquisition-related contingent consideration payments	(27,289)	(2,180)
Funds returned from escrow for MyHammer tender offer	10,604	0
Decrease in restricted cash related to bond redemptions	20,141	20,000
Other, net	(5,002)	(766)
Net cash used in financing activities	(462,055)	(380,731)
Total cash used	(83,215)	(292,884)
Effect of exchange rate changes on cash and cash equivalents	9,345	1,221
Net decrease in cash and cash equivalents	(73,870)	(291,663)
Cash and cash equivalents at beginning of period	1,329,187	1,481,447
Cash and cash equivalents at end of period	$ 1,255,317	$ 1,189,784

CONSOLIDATED STATEMENT OF CASH9

CONSOLIDATED STATEMENT OF CASH FLOWS (Unaudited) (Parenthetical)	Sep. 30, 2017	Sep. 30, 2016
6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes) | Senior Notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)	6.375%	6.375%

THE COMPANY AND SUMMARY OF SIGN

THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations IAC is a leading media and Internet company comprised of widely known consumer brands such as Vimeo, Dotdash (formerly About.com), Dictionary.com, The Daily Beast and Investopedia, along with ANGI Homeservices Inc., which operates HomeAdvisor and Angie's List, and Match Group's online dating portfolio, which includes Match, Tinder, PlentyOfFish and OkCupid. All references to "IAC," the "Company," "we," "our" or "us" in this report are to IAC/InterActiveCorp. On September 29, 2017, the Company completed its previously announced combination (the "Combination") of the businesses in the Company's HomeAdvisor segment and Angie's List, Inc. ("Angie's List") under a new publicly traded company called ANGI Homeservices Inc. ("ANGI Homeservices"). At September 30, 2017, IAC owned 87.1% and 98.5% of the economic and voting interest, respectively, of ANGI Homeservices. See " Note 3—Business Combination " for further information. In connection with the transaction, the Company changed the name of the HomeAdvisor segment to ANGI Homeservices and year-over-year comparisons for financial results for this segment are to the historical results of the HomeAdvisor segment (adjusted to reflect corporate allocations from IAC). In connection with the Combination and in consideration for the transfer by USANi LLC, a wholly-owned subsidiary of the Company ("USANi"), to the Company of all common membership units of HomeAdvisor International, LLC held by USANi, on September 29, 2017, the Company issued a total of 67,633 shares of Series C Cumulative Preferred Stock (the “Series C Preferred Stock”) to USANi. The Company established the Series C Preferred Stock, par value $0.01 per share, on September 28, 2017. The Series C Preferred Stock is entitled to receive a cash dividend of $75.00 per share per annum, payable quarterly in arrears. The outstanding Series C Preferred Stock eliminates in the Company's consolidated financial statements. On March 31, 2017, Match Group sold its non-dating business, consisting of The Princeton Review. The non-dating business does not meet the threshold to be reflected as a discontinued operation at the IAC level. The Company moved the non-dating business to its “Other” segment effective March 31, 2017 and prior period segment data has been recast to conform to this presentation. Basis of Presentation The Company prepares its consolidated financial statements in accordance with U.S. generally accepted accounting principles ("GAAP"). Basis of Consolidation and Accounting for Investments The consolidated financial statements include the accounts of the Company, all entities that are wholly-owned by the Company and all entities in which the Company has a controlling financial interest. Intercompany transactions and accounts have been eliminated. Investments in the common stock or in-substance common stock of entities in which the Company has the ability to exercise significant influence over the operating and financial matters of the investee, but does not have a controlling financial interest, are accounted for using the equity method and are included in "Long-term investments" in the accompanying consolidated balance sheet. In management's opinion, the unaudited interim consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and reflect all adjustments, consisting of normal and recurring adjustments, necessary for the fair presentation of our financial position, results of operations and cash flows for the periods presented. Interim results are not necessarily indicative of the results that may be expected for the full year. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company's Current Report on Form 8-K dated July 18, 2017. Accounting Estimates Management of the Company is required to make certain estimates, judgments and assumptions during the preparation of its consolidated financial statements in accordance with GAAP. These estimates, judgments and assumptions impact the reported amounts of assets, liabilities, revenue and expenses and the related disclosure of contingent assets and liabilities. On an ongoing basis, the Company evaluates its estimates and judgments including those related to: the recoverability of goodwill and indefinite-lived intangible assets; the useful lives and recoverability of definite-lived intangible assets and property and equipment; the fair value of long-term investments; the carrying value of accounts receivable, including the determination of the allowance for doubtful accounts; the determination of revenue reserves; the fair value of acquisition-related contingent consideration arrangements; the liabilities for uncertain tax positions; the valuation allowance for deferred income tax assets; and the fair value of and forfeiture rates for stock-based awards, among others. The Company bases its estimates and judgments on historical experience, its forecasts and budgets and other factors that the Company considers relevant. Actual results could differ from these estimates. Certain Risks and Concentrations A meaningful portion of the Company's revenue is derived from online advertising, the market for which is highly competitive and rapidly changing. Significant changes in this industry or changes in advertising spending behavior or in customer buying behavior could adversely affect our operating results. Most of the Company's online advertising revenue is attributable to a services agreement with Google Inc. ("Google"). For the three and nine months ended September 30, 2017 , revenue from Google represents 21% and 23% , respectively, of the Company's consolidated revenue. For the three and nine months ended September 30, 2016 , revenue from Google represents 23% and 27% , respectively, of the Company's consolidated revenue. The services agreement became effective on April 1, 2016, following the expiration of the previous services agreement, and expires on March 31, 2020; however, the Company may choose to terminate the agreement effective March 31, 2019. The services agreement requires that the Company comply with certain guidelines promulgated by Google. Google may generally unilaterally update its policies and guidelines without advance notice, which could in turn require modifications to, or prohibit and/or render obsolete certain of our products, services and/or business practices, which could be costly to address or otherwise have an adverse effect on our business, financial condition and results of operations. For the three and nine months ended September 30, 2017 , revenue earned from Google was $176.8 million and $539.2 million , respectively. For the three and nine months ended September 30, 2016 , revenue earned from Google was $172.0 million and $638.2 million , respectively. This revenue is earned by the businesses comprising the Applications and Publishing segments. For the three and nine months ended September 30, 2017 , revenue earned from Google represents 82% and 83% of Applications revenue and 72% and 71% of Publishing revenue. For the three and nine months ended September 30, 2016 , revenue earned from Google represents 85% and 87% of Applications revenue and 66% and 76% of Publishing revenue, respectively. Accounts receivable related to revenue earned from Google totaled $62.0 million and $65.8 million at September 30, 2017 and December 31, 2016 , respectively. Recent Accounting Pronouncements Accounting Pronouncements not yet adopted by the Company In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers, which clarifies the principles for recognizing revenue and develops a common standard for all industries. ASU No. 2014-09 was subsequently amended during 2015, 2016 and 2017; these amendments provide further revenue recognition guidance related to principal versus agent considerations, performance obligations and licensing, narrow-scope improvements and practical expedients. ASU No. 2014-09 is a comprehensive revenue recognition standard that will supersede nearly all existing revenue recognition guidance under GAAP. The new standard provides a single principles-based, five-step model to be applied to all contracts with customers. This five-step model includes (1) identifying the contract(s) with the customer, (2) identifying the performance obligations in the contract, (3) determining the transaction price, (4) allocating the transaction price to the performance obligations in the contract and (5) recognizing revenue when each performance obligation is satisfied. More specifically, revenue will be recognized when promised goods or services are transferred to the customer in an amount that reflects the consideration expected in exchange for those goods or services. ASU No. 2014-09 is effective for interim and annual reporting periods beginning after December 15, 2017, with early adoption permitted for interim and annual reporting periods beginning after December 15, 2016. Upon adoption, ASU No. 2014-09 may either be applied retrospectively to each prior period presented or using the modified retrospective approach with the cumulative effect recognized as of the date of initial application. While the Company’s evaluation of the impact the adoption of ASU No. 2014-09 on its consolidated financial statements continues, it has progressed to the point where we have reached certain preliminary determinations. • The Company will adopt ASU No. 2014-09 using the modified retrospective approach effective January 1, 2018. Therefore, the cumulative effect of adoption will be reflected as an adjustment to beginning retained earnings in the Form 10-Q for the period ending March 31, 2018. • The Company’s assessment of the accounting for mobile app store fees incurred by Match Group in connection with obtaining members is still preliminary and ongoing. Match Group currently capitalizes these costs and amortizes them over the period of the applicable membership periods, which generally range from one to six months. The Company’s initial conclusions in applying ASU No. 2014-09 to these costs were: (1) these costs represent the incremental direct costs of obtaining a membership contract and (2) would, therefore, continue to be capitalized and amortized as incurred. The Company is reassessing this conclusion in light of its finding that there are divergent and evolving interpretations of the correct application of ASU No. 2014-09 to these costs. The total capitalized mobile app store fees were $19.8 million as of September 30, 2017. • Within ANGI Homeservices, the effect of the adoption of ASU No. 2014-09 on HomeAdvisor will be that sales commissions, which represent the incremental direct costs of obtaining a service professional contract, will be capitalized and amortized over the average life of a service professional. These costs are expensed as incurred today. Prior to the Combination, Angie's List capitalized sales commissions and amortized the cost over the term of the applicable advertising contract. Following the Combination, Angie's List accounting policies will be conformed to the Company's accounting policies and these costs will be expensed as incurred. Following the adoption of ASU No. 2014-09, these costs will be capitalized and amortized over the average life of a service professional. • Within Applications, the primary effect of the adoption of ASU No. 2014-09 will be to accelerate the recognition of the portion of the revenue of certain desktop applications sold by SlimWare that qualify as functional intellectual property under ASU No. 2014-09. This revenue is currently deferred and recognized over the applicable subscription term. The Company does not expect the adoption of ASU No. 2014-09 to have a material effect on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) , which supersedes existing guidance on accounting for leases in "Leases (Topic 840)" and generally requires all leases to be recognized in the statement of financial position. The provisions of ASU No. 2016-02 are effective for reporting periods beginning after December 15, 2018; early adoption is permitted. The provisions of ASU No. 2016-02 are to be applied using a modified retrospective approach. The Company will adopt ASU No. 2016-02 effective January 1, 2019. The Company is currently evaluating the impact the adoption of this standard update will have on its consolidated financial statements. Accounting Pronouncements adopted by the Company In May 2017, the FASB issued ASU No. 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting , which provides guidance about the changes to the terms and conditions of a share-based payment award that require an entity to apply modification accounting in "Stock Compensation (Topic 718)." The provisions of ASU No. 2017-09 are effective for reporting periods beginning after December 15, 2017; early adoption is permitted. The provisions of ASU No. 2017-09 are to be applied prospectively to an award modified on or after the adoption date. The Company early adopted the provisions of ASU No. 2017-09 during the third quarter of 2017 and the adoption of this standard update did not have a material impact on its consolidated financial statements. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments , which clarifies how cash receipts and cash payments in certain transactions are presented and classified on the statement of cash flows. The provisions of ASU No. 2016-15 are effective for reporting periods beginning after December 15, 2017, including interim periods, and will require adoption on a retrospective basis unless it is impracticable to apply, in which case we would be required to apply the amendments prospectively as of the earliest date practicable; early adoption is permitted. Upon adoption, cash payments made soon after the acquisition date of a business to settle a contingent consideration liability are classified as cash outflows for investing activities. Cash payments which are not made soon after the acquisition date of a business to settle a contingent consideration liability are separated and classified as cash outflows for financing activities up to the amount of the contingent consideration liability recognized at the acquisition date and as cash outflows from operating activities for any excess. The Company early adopted the provisions of ASU No. 2016-15 on January 1, 2017. As a result, $11.1 million of an acquisition-related contingent consideration payment of $15.0 million , which was in excess of the liability initially recognized at the acquisition date, has been classified as a cash outflow within net cash provided by operating activities in the accompanying consolidated statement of cash flows for the nine months ended September 30, 2017. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . The Company adopted the provisions of ASU No. 2016-09 on January 1, 2017. Excess tax benefits or deficiencies related to equity awards to employees upon the exercise of stock options and the vesting of restricted stock units after January 1, 2017 are (i) reflected in the consolidated statement of operations as a component of the provision for income taxes, rather than recognized in equity, and (ii) reflected as operating, rather than financing, cash flows in our consolidated statement of cash flows. Excess tax benefits for the nine months ended September 30, 2017 were $314.3 million . Excess tax benefits of $43.1 million for the nine months ended September 30, 2016 were reclassified in the consolidated statement of cash flows to conform to the current year presentation. Upon adoption, the calculation of fully diluted shares excludes excess tax benefits from the assumed proceeds in applying the treasury stock method; previously such benefits were included in the calculation. This change increased fully diluted shares by approximately 1.1 million and 2.0 million shares for the three and nine months ended September 30, 2017 , respectively. The Company continues to account for forfeitures using an estimated forfeiture rate. In January 2017, the FASB issued ASU No. 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment , which is intended to simplify the accounting for goodwill impairment. The guidance eliminates the requirement to calculate the implied fair value of goodwill under today’s two-step impairment test to measure a goodwill impairment charge. The provisions of ASU No. 2017-04 are effective for reporting periods beginning after December 15, 2019; early adoption is permitted. The provisions of ASU No. 2017-04 are to be applied using a prospective approach. The Company early adopted the provisions of ASU No. 2017-04 on January 1, 2017 and the adoption of this standard update did not have a material impact on its consolidated financial statements. Reclassifications Certain prior year amounts have been reclassified to conform to the current year presentation.

INCOME TAXES

INCOME TAXES	9 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES At the end of each interim period, the Company makes its best estimate of the annual expected effective income tax rate and applies that rate to its ordinary year-to-date earnings or loss. The income tax provision or benefit related to significant, unusual, or extraordinary items, if applicable, that will be separately reported or reported net of their related tax effects are individually computed and recognized in the interim period in which they occur. In addition, the effect of changes in enacted tax laws or rates, tax status, judgment on the realizability of a beginning-of-the-year deferred tax asset in future years or the liabilities for uncertain tax positions is recognized in the interim period in which the change occurs. The computation of the annual expected effective income tax rate at each interim period requires certain estimates and assumptions including, but not limited to, the expected pre-tax income (or loss) for the year, projections of the proportion of income (and/or loss) earned and taxed in foreign jurisdictions, permanent and temporary differences, and the likelihood of the realization of deferred tax assets generated in the current year. The accounting estimates used to compute the provision or benefit for income taxes may change as new events occur, more experience is acquired, additional information is obtained or our tax environment changes. To the extent that the expected annual effective income tax rate changes during a quarter, the effect of the change on prior quarters is included in income tax provision in the quarter in which the change occurs. For the three and nine months ended September 30, 2017 , the Company recorded an income tax benefit of $279.5 million and $322.8 million , respectively. The income tax benefit for the three and nine months ended September 30, 2017 is due primarily to the effect of adopting the provisions of ASU No. 2016-09 on January 1, 2017. Under ASU No. 2016-09, excess tax benefits generated by the exercise, purchase or settlement of stock-based awards of $314.3 million for the nine months ended September 30, 2017 are recognized as a reduction to the income tax provision rather than as an increase to additional paid-in capital. For the three and nine months ended September 30, 2016 , the Company recorded an income tax provision of $17.8 million and an income tax benefit of $77.4 million , respectively, which represents effective income tax rates of 25% and 37% , respectively. The effective tax rate for the three months ended September 30, 2016 is lower than the statutory rate of 35% due primarily to foreign income taxed at lower rates. The effective tax rate for the nine months ended September 30, 2016 is higher than the statutory rate of 35% due primarily to foreign income taxed at lower rates, state taxes and the non-taxable gain on the sale of PriceRunner, partially offset by the non-deductible portion of the goodwill impairment at the Publishing segment. The Company recognizes interest and, if applicable, penalties related to unrecognized tax benefits in the income tax provision. At September 30, 2017 and December 31, 2016 , the Company has accrued $3.3 million and $2.6 million , respectively, for the payment of interest. At both September 30, 2017 and December 31, 2016 , the Company has accrued $1.7 million for penalties. The Company is routinely under audit by federal, state, local and foreign authorities in the area of income tax. These audits include questioning the timing and the amount of income and deductions and the allocation of income and deductions among various tax jurisdictions. The Internal Revenue Service is currently auditing the Company’s federal income tax returns for the years ended December 31, 2010 through 2012. The statute of limitations for the years 2010 through 2013 has been extended to June 30, 2018. Various other jurisdictions are open to examination for tax years beginning with 2009. Income taxes payable include reserves considered sufficient to pay assessments that may result from examination of prior year tax returns. Changes to reserves from period to period and differences between amounts paid, if any, upon resolution of audits and amounts previously provided may be material. Differences between the reserves for income tax contingencies and the amounts owed by the Company are recorded in the period they become known. At September 30, 2017 and December 31, 2016 , unrecognized tax benefits, including interest and penalties, are $43.0 million and $41.0 million , respectively. If unrecognized tax benefits at September 30, 2017 are subsequently recognized, $39.4 million , net of related deferred tax assets and interest, would reduce income tax expense. The comparable amount as of December 31, 2016 was $37.7 million . The Company believes that it is reasonably possible that its unrecognized tax benefits could decrease by $22.5 million by June 30, 2018, due to expirations of statutes of limitations; $22.0 million of which would reduce the income tax provision. The Company regularly assesses the realizability of deferred tax assets considering all available evidence including, among other things, the nature, frequency and severity of prior cumulative losses, forecasts of future taxable income, the duration of statutory carryforward periods, available tax planning and historical experience, to the extent these items are applicable. As of September 30, 2017 , the Company has a gross deferred tax asset of $221.5 million that the Company expects to fully utilize on a more likely than not basis.

BUSINESS COMBINATION

BUSINESS COMBINATION	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
BUSINESS COMBINATION	BUSINESS COMBINATION On September 29, 2017, the Company completed its previously announced combination of the businesses in the Company's HomeAdvisor segment and Angie's List under a new publicly traded company called ANGI Homeservices. Through the Combination, ANGI Homeservices acquired 100% of the common stock of Angie's List on September 29, 2017 for a total purchase price valued at $781.4 million . Angie’s List is a nationwide marketplace for local services where consumers can research, hire, rate and review the providers of these services. Ratings and reviews assist members in identifying and hiring a provider for their local service needs. Angie’s List's services are provided in markets located across the continental United States. The purchase price of $781.4 million was determined based on the sum of (i) the fair value of the 61.3 million shares of Angie's List common stock outstanding immediately prior to the Combination based on the closing stock price of Angie's List common stock on the NASDAQ on September 29, 2017 of $12.46 per share; (ii) the cash consideration of $1.9 million paid to holders of Angie's List common stock who elected to receive $8.50 in cash per share; and (iii) the fair value of vested equity awards (including the pro rata portion of unvested awards attributable to pre-combination services) outstanding under Angie's List stock plans on September 29, 2017. Each stock option to purchase shares of Angie's List common stock that was outstanding immediately prior to the effective time of the Combination was, as of the effective time of the Combination, converted into an option to purchase (i) that number of Class A shares of ANGI Homeservices equal to the total number of shares of Angie's List common stock subject to such Angie's List option immediately prior to the effective time of the Combination, (ii) at a per-share exercise price equal to the exercise price per share of Angie's List common stock at which such Angie's List option was exercisable immediately prior to the effective time of the Combination. Each award of Angie's List restricted stock units that was outstanding immediately prior to the effective time of the Combination was, as of the effective time of the Combination, converted into an ANGI Homeservices restricted stock unit award with respect to a number of Class A shares of ANGI Homeservices equal to the total number of shares of Angie's List common stock subject to such Angie's List restricted stock unit award immediately prior to the effective time of the Combination. The table below summarizes the purchase price: Angie's List (In thousands) Class A common stock $ 763,684 Cash consideration for holders who elected to receive $8.50 in cash per share of Angie's List common stock 1,913 Fair value of vested and pro rata portion of unvested stock options attributable to pre-combination services 11,749 Fair value of the pro rata portion of unvested restricted stock units attributable to pre-combination services 4,038 Total purchase price $ 781,384 The financial results of Angie's List are included in the Company's consolidated financial statements, within the ANGI Homeservices segment, beginning September 29, 2017. For the three and nine months ended September 30, 2017 , the Company included $0.7 million of revenue and $20.0 million of net losses in its consolidated statement of operations related to Angie's List. The Company is in the process of completing its determination of the fair values of assets acquired and liabilities assumed and the preliminary fair values are subject to revision. These fair values are expected to be finalized in the fourth quarter of 2017. The table below summarizes the preliminary estimated fair values of the assets acquired and liabilities assumed at the date of combination: Angie's List (In thousands) Cash and cash equivalents $ 44,270 Other current assets 10,641 Property and equipment 16,341 Goodwill 545,396 Intangible assets 317,300 Total assets 933,948 Deferred revenue (32,130 ) Other current liabilities (46,106 ) Long-term debt—related party (61,498 ) Deferred income taxes (11,478 ) Other long-term liabilities (1,352 ) Net assets acquired $ 781,384 The purchase price was based on the expected financial performance of Angie's List, not on the value of the net identifiable assets at the time of combination. This resulted in a significant portion of the purchase price being attributed to goodwill because Angie's List is complementary and synergistic to the other North America businesses of ANGI Homeservices. The preliminary estimated fair values of the identifiable intangible assets acquired at the date of combination are as follows: Angie's List (In thousands) Weighted-average useful life (years) Indefinite-lived trade names and trademarks $ 137,000 Indefinite Service providers 90,500 3 Developed technology 63,900 6 Memberships 15,900 3 User base 10,000 1 Total identifiable intangible assets acquired $ 317,300 Other current assets, current liabilities and other long-term liabilities of Angie's List were reviewed and adjusted to their fair values at the date of combination, as necessary. The fair value of deferred revenue was determined using an income approach that utilized a cost to fulfill analysis. The fair values of trade names and trademarks were determined using an income approach that utilized the relief from royalty methodology. The fair values of developed technology and user base were determined using a cost approach that utilized the cost to replace methodology. The fair values of the service providers and memberships were determined using an income approach that utilized the excess earnings methodology. The valuations of deferred revenue and intangible assets incorporate significant unobservable inputs and require significant judgment and estimates, including the amount and timing of future cash flows, cost and profit margins related to deferred revenue and the determination of royalty and discount rates. The amount attributed to goodwill is not tax deductible. Pro forma financial information The unaudited pro forma financial information in the table below presents the combined results of the Company and Angie's List as if the Combination had occurred on January 1, 2016. The unaudited pro forma financial information includes adjustments required under the acquisition method of accounting and is presented for informational purposes only and is not necessarily indicative of the results that would have been achieved had the Combination actually occurred on January 1, 2016. For the three and nine months ended September 30, 2017 , pro forma adjustments include (i) reductions in stock-based compensation expense of $85.1 million and $52.8 million , respectively, and transaction related costs of $22.1 million and $25.6 million , respectively, because they are one-time in nature and will not have a continuing impact on operations; and (ii) an increase in amortization of intangibles of $11.4 million and $34.4 million , respectively. The stock-based compensation expense is related to the modification of previously issued HomeAdvisor vested equity awards, which were converted into ANGI Homeservices' equity awards, and the acceleration of previously issued Angie's List equity awards held by employees terminated in connection with the Combination. The transaction related costs include severance and retention costs of $12.0 million related to the Combination. For the three and nine months ended September 30, 2016 , pro forma adjustments include a reduction in revenue of $5.0 million and $31.4 million , respectively, due to the write-off of deferred revenue at the date of acquisition as well as increases in stock-based compensation expense of $19.7 million and $51.4 million , respectively, and amortization of intangibles of $14.0 million and $42.1 million , respectively. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands, except per share data) Revenue $ 898,584 $ 838,834 $ 2,571,613 $ 2,544,019 Net earnings (loss) attributable to IAC shareholders 244,400 12,237 313,054 (221,446 ) Basic earnings (loss) per share attributable to IAC shareholders 3.02 0.15 3.94 (2.76 ) Diluted earnings (loss) per share attributable to IAC shareholders 2.80 0.15 3.70 (2.76 )

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS	9 Months Ended
	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS	GOODWILL AND INTANGIBLE ASSETS Goodwill and intangible assets, net are as follows: September 30, December 31, 2017 2016 (In thousands) Goodwill $ 2,501,589 $ 1,924,052 Intangible assets with indefinite lives 460,333 320,645 Intangible assets with definite lives, net 199,770 34,806 Total goodwill and intangible assets, net $ 3,161,692 $ 2,279,503 The following table presents the balance of goodwill by reportable segment, including the changes in the carrying value of goodwill, for the nine months ended September 30, 2017 : Balance at Additions (Deductions) Foreign Balance at (In thousands) Match Group $ 1,206,538 $ 255 $ — $ 43,575 $ 1,250,368 ANGI Homeservices 170,611 593,880 — 7,865 772,356 Video 25,239 6,384 — — 31,623 Applications 447,242 — — — 447,242 Other 74,422 — (74,430 ) 8 — Total $ 1,924,052 $ 600,519 $ (74,430 ) $ 51,448 $ 2,501,589 The additions primarily relate to the acquisitions of Angie's List, MyBuilder and HomeStars (included in the ANGI Homeservices segment). The deductions relate to the sale of The Princeton Review (previously included in the Other segment). The following table presents the balance of goodwill by reportable segment, including the changes in the carrying value of goodwill, for the year ended December 31, 2016 : Balance at Additions (Deductions) Impairment Foreign Balance at (In thousands) Match Group $ 1,218,607 $ 603 $ (2,983 ) $ — $ (9,689 ) $ 1,206,538 ANGI Homeservices 150,251 21,985 — — (1,625 ) 170,611 Video 15,590 9,649 — — — 25,239 Applications 447,242 — — — — 447,242 Publishing 277,192 — (1,968 ) (275,367 ) 143 — Other 136,482 — (62,860 ) — 800 74,422 Total $ 2,245,364 $ 32,237 $ (67,811 ) $ (275,367 ) $ (10,371 ) $ 1,924,052 The additions primarily relate to the acquisitions of MyHammer Holding AG (included in the ANGI Homeservices segment) and VHX (included in the Video segment). The deductions primarily relate to the sales of PriceRunner and ShoeBuy (both included in the Other segment). During the second quarter of 2016, the Company recorded impairment charges related to the entire $275.4 million balance of the Publishing reporting unit goodwill. The goodwill impairment charge at Publishing was driven by the impact from the new Google services agreement, traffic trends and monetization challenges and the corresponding impact on the current estimate of fair value. The September 30, 2017 and December 31, 2016 goodwill balance reflects accumulated impairment losses of $598.0 million , $529.1 million and $11.6 million at Publishing, Applications and Connected Ventures (included in the Video segment), respectively. Intangible assets with indefinite lives are trade names and trademarks acquired in various acquisitions. At September 30, 2017 and December 31, 2016 , intangible assets with definite lives are as follows: September 30, 2017 Gross Accumulated Net Weighted-Average (In thousands) Advertiser and supplier relationships and other $ 119,029 $ (4,654 ) $ 114,375 3.0 Technology 104,876 (32,348 ) 72,528 4.9 Customer lists and user base 13,911 (2,973 ) 10,938 1.1 Content 5,000 (3,723 ) 1,277 5.0 Trade names 14,518 (13,866 ) 652 2.7 Total $ 257,334 $ (57,564 ) $ 199,770 3.7 December 31, 2016 Gross Accumulated Net Weighted-Average (In thousands) Advertiser and supplier relationships and other $ 7,230 $ (2,612 ) $ 4,618 4.5 Technology 38,602 (27,667 ) 10,935 3.4 Customer lists 12,485 (9,997 ) 2,488 3.7 Content 14,802 (8,965 ) 5,837 4.3 Trade names 63,855 (52,927 ) 10,928 1.8 Total $ 136,974 $ (102,168 ) $ 34,806 2.8 At September 30, 2017 , amortization of intangible assets with definite lives for each of the next five years is estimated to be as follows: Years Ending September 30, (In thousands) 2018 $ 68,567 2019 51,422 2020 47,775 2021 10,735 2022 10,650 Thereafter 10,621 Total $ 199,770

FAIR VALUE MEASUREMENTS AND FIN

FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS	FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS The Company categorizes its financial instruments measured at fair value into a fair value hierarchy that prioritizes the inputs used in pricing the asset or liability. The three levels of the fair value hierarchy are: • Level 1: Observable inputs obtained from independent sources, such as quoted prices for identical assets and liabilities in active markets. • Level 2: Other inputs, which are observable directly or indirectly, such as quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active and inputs that are derived principally from or corroborated by observable market data. The fair values of the Company's Level 2 financial assets are primarily obtained from observable market prices for identical underlying securities that may not be actively traded. Certain of these securities may have different market prices from multiple market data sources, in which case an average market price is used. • Level 3: Unobservable inputs for which there is little or no market data and require the Company to develop its own assumptions, based on the best information available in the circumstances, about the assumptions market participants would use in pricing the assets or liabilities. See below for a discussion of fair value measurements made using Level 3 inputs. The following tables present the Company's financial instruments that are measured at fair value on a recurring basis: September 30, 2017 Quoted Market Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Measurements (In thousands) Assets: Cash equivalents: Money market funds $ 865,630 $ — $ — $ 865,630 Time deposits — 105,942 — 105,942 Treasury discount notes 1,199 — — 1,199 Certificates of deposit — 6,199 — 6,199 Total $ 866,829 $ 112,141 $ — $ 978,970 Liabilities: Contingent consideration arrangement $ — $ — $ (1,792 ) $ (1,792 ) December 31, 2016 Quoted Market Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Measurements (In thousands) Assets: Cash equivalents: Money market funds $ 667,662 $ — $ — $ 667,662 Commercial paper — 123,640 — 123,640 Time deposits — 79,000 — 79,000 Treasury discount notes 24,991 — — 24,991 Marketable securities: Commercial paper — 49,797 — 49,797 Treasury discount notes 34,974 — — 34,974 Corporate debt securities — 4,571 — 4,571 Total $ 727,627 $ 257,008 $ — $ 984,635 Liabilities: Contingent consideration arrangements $ — $ — $ (33,871 ) $ (33,871 ) The following tables present the changes in the Company's financial instruments that are measured at fair value on a recurring basis using significant unobservable inputs (Level 3): Contingent Consideration Arrangements Three Months Ended September 30, 2017 2016 (In thousands) Balance at July 1 $ (24,829 ) $ (45,526 ) Total net (losses) gains: Included in earnings: Fair value adjustments (60 ) 2,477 Included in other comprehensive loss (332 ) (333 ) Settlements 23,429 30 Balance at September 30 $ (1,792 ) $ (43,352 ) Nine Months Ended September 30, 2017 2016 Contingent Consideration Arrangements Auction Rate Security Contingent Consideration Arrangements (In thousands) Balance at January 1 $ (33,871 ) $ 4,050 $ (33,873 ) Total net (losses) gains: Included in earnings: Fair value adjustments (4,945 ) — (7,993 ) Included in other comprehensive (loss) income (1,405 ) 5,950 (5,614 ) Fair value at date of acquisition — — 1,948 Settlements 38,429 — 2,180 Proceeds from sale — (10,000 ) — Balance at September 30 $ (1,792 ) $ — $ (43,352 ) Contingent Consideration Arrangements As of September 30, 2017 , there is one contingent consideration arrangement related to a business acquisition. The maximum contingent payment related to this arrangement is $3.0 million and the gross fair value of this arrangement, before the unamortized discount, at September 30, 2017 is $2.1 million . The sole remaining contingent consideration arrangement is based upon earnings performance. Previous contingent consideration arrangements were based upon earnings performance and/or operating metrics. The Company determined the fair value of the contingent consideration arrangement by using probability-weighted analyses to determine the amounts of the gross liability, and, because the arrangement was initially long-term in nature, applying a discount rate that appropriately captures the risks associated with the obligation to determine the net amount reflected in the consolidated financial statements. The fair values of the contingent consideration arrangements at both September 30, 2017 and December 31, 2016 reflect discount rates of 12% . The fair value of contingent consideration arrangements is sensitive to changes in the forecasts of earnings and/or the relevant operating metrics and changes in discount rates. The Company remeasures the fair value of the contingent consideration arrangements each reporting period, including the accretion of the discount, if applicable, and changes are recognized in “General and administrative expense” in the accompanying consolidated statement of operations. The contingent consideration arrangement liability at September 30, 2017 and December 31, 2016 includes a current portion of $0.6 million and $33.4 million , respectively, and a non-current portion of $1.2 million and $0.4 million , respectively, which are included in “Accrued expenses and other current liabilities” and “Other long-term liabilities,” respectively, in the accompanying consolidated balance sheet. Assets measured at fair value on a nonrecurring basis The Company's non-financial assets, such as goodwill, intangible assets and property and equipment, as well as equity and cost method investments, are adjusted to fair value only when an impairment charge is recognized. Such fair value measurements are based predominantly on Level 3 inputs. Cost method investments At September 30, 2017 and December 31, 2016 , the carrying values of the Company's investments accounted for under the cost method totaled $116.2 million and $116.1 million , respectively, and are included in "Long-term investments" in the accompanying consolidated balance sheet. The Company evaluates each cost method investment for impairment on a quarterly basis and recognizes an impairment loss if a decline in value is determined to be other-than-temporary. If the Company has not identified events or changes in circumstances that may have a significant adverse effect on the fair value of a cost method investment, then the fair value of such cost method investment is not estimated, as it is impracticable to do so. Financial instruments measured at fair value only for disclosure purposes The following table presents the carrying value and the fair value of financial instruments measured at fair value only for disclosure purposes: September 30, 2017 December 31, 2016 Carrying Fair Carrying Fair (In thousands) Current portion of long-term debt $ — $ — $ (20,000 ) $ (20,311 ) Long-term debt, net of current portion (1,649,267 ) (1,720,311 ) (1,582,484 ) (1,657,861 ) The fair value of long-term debt, including the current portion, is estimated using market prices or indices for similar liabilities and takes into consideration other factors such as credit quality and maturity, which are Level 3 inputs.

LONG-TERM DEBT

LONG-TERM DEBT	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Long-term debt consists of: September 30, 2017 December 31, 2016 (In thousands) Match Group Debt: 6.75% Senior Notes due December 15, 2022 (the "Match Group 6.75% Senior Notes"); interest payable each June 15 and December 15, which commenced June 15, 2016 $ 445,172 $ 445,172 6.375% Senior Notes due June 1, 2024 (the "Match Group 6.375% Senior Notes"); interest payable each June 1 and December 1, which commenced December 1, 2016 400,000 400,000 Match Group Term Loan due November 16, 2022 (a) 425,000 350,000 Total Match Group long-term debt 1,270,172 1,195,172 Less: Unamortized original issue discount and original issue premium, net 4,470 5,245 Less: Unamortized debt issuance costs 11,704 13,434 Total Match Group debt 1,253,998 1,176,493 IAC Debt: 4.875% Senior Notes due November 30, 2018 (the "4.875% Senior Notes"); interest payable each May 30 and November 30, which commenced May 30, 2014 361,874 390,214 4.75% Senior Notes due December 15, 2022 (the "4.75% Senior Notes"); interest payable each June 15 and December 15, which commenced June 15, 2013 34,859 38,109 Total IAC long-term debt 396,733 428,323 Less: Current portion of IAC long-term debt — 20,000 Less: Unamortized debt issuance costs 1,464 2,332 Total IAC debt, net of current portion 395,269 405,991 Total long-term debt, net of current portion $ 1,649,267 $ 1,582,484 ________________________ (a) The Match Group Term Loan matures on November 16, 2022; provided that, if any of the Match Group 6.75% Senior Notes remain outstanding on the date that is 91 days prior to the maturity date of the Match Group 6.75% Senior Notes, the Match Group Term Loan maturity date shall be September 15, 2022, the date that is 91 days prior to the maturity date of the Match Group 6.75% Senior Notes. Match Group Senior Notes The Match Group 6.375% Senior Notes were issued on June 1, 2016. The proceeds of $400 million were used to prepay a portion of indebtedness outstanding under the Match Group Term Loan. At any time prior to June 1, 2019, these notes may be redeemed at a redemption price equal to the sum of the principal amount thereof, plus accrued and unpaid interest and a make-whole premium. Thereafter, these notes may be redeemed at redemption prices set forth in the indenture governing the notes, together with accrued and unpaid interest thereon to the applicable redemption date. The Match Group 6.75% Senior Notes were issued on November 16, 2015, in exchange for a portion of the 4.75% Senior Notes (the "Match Exchange Offer"). At any time prior to December 15, 2017, the Match Group 6.75% Senior Notes may be redeemed at a redemption price equal to the sum of the principal amount thereof, plus accrued and unpaid interest and a make-whole premium. Thereafter, these notes may be redeemed at redemption prices set forth in the indenture governing the notes, together with accrued and unpaid interest thereon to the applicable redemption date. The indentures governing the Match Group 6.375% and 6.75% Senior Notes contain covenants that would limit Match Group's ability to pay dividends or to make distributions and repurchase or redeem Match Group stock in the event a default has occurred or Match Group's leverage ratio (as defined in the indentures) exceeds 5.0 to 1.0 . At September 30, 2017 , there were no limitations pursuant thereto. There are additional covenants that limit Match Group's ability and the ability of its subsidiaries to, among other things, (i) incur indebtedness, make investments, or sell assets in the event Match Group is not in compliance with the leverage ratio set forth in the indenture, and (ii) incur liens, enter into agreements restricting Match Group subsidiaries' ability to pay dividends, enter into transactions with affiliates and consolidate, merge or sell substantially all of their assets. Match Group Term Loan and Match Group Credit Facility On November 16, 2015, under a credit agreement (the "Match Group Credit Agreement"), Match Group borrowed $800 million in the form of a term loan (the "Match Group Term Loan"). On March 31, 2016, Match Group made a $10 million principal payment on the Match Group Term Loan. On June 1, 2016, the $400 million in proceeds from the Match Group 6.375% Senior Notes, described above, were used to repay a portion of the Match Group Term Loan. On December 8, 2016, Match Group made an additional $40 million principal payment on the Match Group Term Loan and the remaining outstanding balance of $350 million , which was due at maturity, was repriced. On August 14, 2017, the Match Group Term Loan was increased by $75 million . In addition, the outstanding balance of $425 million was repriced at LIBOR plus 2.50% , and the LIBOR floor was reduced to 0.00% . The Match Group Term Loan provides for additional annual principal payments as part of an excess cash flow sweep provision, the amount of which, if any, is governed by the secured net leverage ratio contained in the Match Group Credit Agreement. The interest rate on the Match Group Term Loan at September 30, 2017 is 3.81% . Interest payments are due at least quarterly through the term of the loan. Match Group has a $500 million revolving credit facility (the "Match Group Credit Facility") that expires on October 7, 2020. At September 30, 2017 and December 31, 2016 , there were no outstanding borrowings under the Match Group Credit Facility. The annual commitment fee on undrawn funds based on the current leverage ratio is 30 basis points. Borrowings under the Match Group Credit Facility bear interest, at Match Group's option, at a base rate or LIBOR, in each case plus an applicable margin, which is determined by reference to a pricing grid based on Match Group's consolidated net leverage ratio. The terms of the Match Group Credit Facility require Match Group to maintain a consolidated net leverage ratio of not more than 5.0 to 1.0 and a minimum interest coverage ratio of not less than 2.5 to 1.0 (in each case as defined in the agreement). There are additional covenants under the Match Group Credit Facility and the Match Group Term Loan that limit the ability of Match Group and its subsidiaries to, among other things, incur indebtedness, pay dividends or make distributions. While the Match Group Term Loan remains outstanding, these same covenants under the Match Group Credit Agreement are more restrictive than the covenants that are applicable to the Match Group Credit Facility. Obligations under the Match Group Credit Facility and Match Group Term Loan are unconditionally guaranteed by certain Match Group wholly-owned domestic subsidiaries, and are also secured by the stock of certain Match Group domestic and foreign subsidiaries. The Match Group Term Loan and outstanding borrowings, if any, under the Match Group Credit Facility rank equally with each other, and have priority over the Match Group 6.75% and 6.375% Senior Notes to the extent of the value of the assets securing the borrowings under the Match Group Credit Agreement. IAC Senior Notes The 4.875% and 4.75% Senior Notes were issued by IAC on November 15, 2013 and December 21, 2012, respectively. The 4.875% and 4.75% Senior Notes are unconditionally guaranteed by certain wholly-owned domestic subsidiaries, which are designated as guarantor subsidiaries; neither Match Group, ANGI Homeservices nor any of their subsidiaries guarantee any debt of IAC, or in the case of Match Group and its subsidiaries are subject to any of the covenants related to such debt. The guarantor subsidiaries are the same for the 4.875% and 4.75% Senior Notes. See " Note 13—Guarantor and Non-guarantor Financial Information " for financial information relating to guarantor and non-guarantor subsidiaries. For the nine months ended September 30, 2017 , the Company redeemed and repurchased $28.3 million of its 4.875% Senior Notes and repurchased $3.3 million of its 4.75% Senior Notes. For the nine months ended September 30, 2016 , the Company redeemed and repurchased $109.8 million of its 4.875% Senior Notes and repurchased $16.5 million of its 4.75% Senior Notes. On October 2, 2017, a subsidiary of the Company issued $517.5 million aggregate principal amount of 0.875% Exchangeable Senior Notes due October 1, 2022, which are guaranteed by the Company. The proceeds from these notes were, in part, loaned to IAC, which repaid the outstanding balance of the 4.875% Senior Notes of $361.9 million . See " Note 14—Subsequent Events " for further information. IAC Credit Facility IAC has a $300.0 million revolving credit facility (the "IAC Credit Facility") that expires October 7, 2020. At September 30, 2017 and December 31, 2016 , there were no outstanding borrowings under the IAC Credit Facility. The annual commitment fee on undrawn funds is currently 35 basis points, and is based on the leverage ratio most recently reported. Borrowings under the IAC Credit Facility bear interest, at the Company's option, at a base rate or LIBOR, in each case, plus an applicable margin, which is determined by reference to a pricing grid based on the Company's leverage ratio. The terms of the IAC Credit Facility require that the Company maintains a leverage ratio (as defined in the agreement) of not more than 3.25 to 1.0 and restrict our ability to incur additional indebtedness. Borrowings under the IAC Credit Facility are unconditionally guaranteed by the same domestic subsidiaries that guarantee the 4.875% and 4.75% Senior Notes and are also secured by the stock of certain of our domestic and foreign subsidiaries. The 4.875% and 4.75% Senior Notes rank equally with each other, and are subordinate to outstanding borrowings under the IAC Credit Facility to extent of the value of the assets securing such borrowings.

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE LOSS	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS The following tables present the components of accumulated other comprehensive (loss) income and items reclassified out of accumulated other comprehensive loss into earnings: Three Months Ended September 30, 2017 Foreign Currency Translation Adjustment Unrealized Gains On Available-For-Sale Securities Accumulated Other Comprehensive (Loss) Income (In thousands) Balance at July 1 $ (136,738 ) $ — $ (136,738 ) Other comprehensive income before reclassifications 37,225 — 37,225 Amounts reclassified to earnings — — — Net current period other comprehensive income 37,225 — 37,225 Balance at September 30 $ (99,513 ) $ — $ (99,513 ) Three Months Ended September 30, 2016 Foreign Currency Translation Adjustment Unrealized Gains (Losses) On Available-For-Sale Securities Accumulated Other Comprehensive Loss (In thousands) Balance at July 1 $ (121,612 ) $ 4,205 $ (117,407 ) Other comprehensive (loss) income before reclassifications, net of tax provision of $0.1 million related to unrealized losses on available-for-sale securities (5,132 ) 114 (5,018 ) Amounts reclassified to earnings — (259 ) (a) (259 ) Net current period other comprehensive loss (5,132 ) (145 ) (5,277 ) Balance at September 30 $ (126,744 ) $ 4,060 $ (122,684 ) ___________________ (a) Amount is net of a tax provision of $0.2 million . Nine Months Ended September 30, 2017 Foreign Currency Translation Adjustment Unrealized Gains On Available-For-Sale Securities Accumulated Other Comprehensive (Loss) Income (In thousands) Balance at January 1 $ (170,149 ) $ 4,026 $ (166,123 ) Other comprehensive income before reclassifications 69,951 7 69,958 Amounts reclassified to earnings 685 (4,033 ) (b) (3,348 ) Net current period other comprehensive income (loss) 70,636 (4,026 ) 66,610 Balance as of September 30 $ (99,513 ) $ — $ (99,513 ) ___________________ (b) Amount includes a tax benefit of $3.8 million . Nine Months Ended September 30, 2016 Foreign Currency Translation Adjustment Unrealized Gains On Available-For-Sale Securities Accumulated Other Comprehensive (Loss) Income (In thousands) Balance as of January 1 $ (154,645 ) $ 2,542 $ (152,103 ) Other comprehensive (loss) income before reclassifications, net of tax benefit of $0.7 million related to unrealized losses on available-for-sale securities (3,538 ) 4,868 1,330 Amounts reclassified to earnings 9,850 (2,892 ) (c) 6,958 Net current period other comprehensive income 6,312 1,976 8,288 Reallocation of accumulated other comprehensive loss (income) related to the noncontrolling interests created in the Match Group initial public offering 21,589 (458 ) 21,131 Balance as of September 30 $ (126,744 ) $ 4,060 $ (122,684 ) ___________________ (c) Amount is net of a tax provision of $0.2 million . At September 30, 2017, there was no tax benefit or provision on the accumulated other comprehensive loss.

EARNINGS (LOSS) PER SHARE

EARNINGS (LOSS) PER SHARE	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
EARNINGS (LOSS) PER SHARE	EARNINGS (LOSS) PER SHARE The following table sets forth the computation of basic and diluted earnings (loss) per share attributable to IAC shareholders: Three Months Ended September 30, 2017 2016 Basic Diluted Basic Diluted (In thousands, except per share data) Numerator: Net earnings $ 225,639 $ 225,639 $ 52,340 $ 52,340 Net earnings attributable to noncontrolling interests (45,996 ) (45,996 ) (9,178 ) (9,178 ) Impact from public subsidiaries' dilutive securities (a) — (23,749 ) — (3,473 ) Net earnings attributable to IAC shareholders $ 179,643 $ 155,894 $ 43,162 $ 39,689 Denominator: Weighted average basic shares outstanding 80,817 80,817 79,532 79,532 Dilutive securities including stock options and RSUs and subsidiary denominated equity awards (b)(c)(e) — 6,379 — 2,087 Denominator for earnings per share—weighted average shares (b)(c)(e) 80,817 87,196 79,532 81,619 Earnings per share attributable to IAC shareholders: Earnings per share $ 2.22 $ 1.79 $ 0.54 $ 0.49 Nine Months Ended September 30, 2017 2016 Basic Diluted Basic Diluted (In thousands, except per share data) Numerator: Net earnings (loss) $ 334,659 $ 334,659 $ (130,268 ) $ (130,268 ) Net earnings attributable to noncontrolling interests (62,539 ) (62,539 ) (13,063 ) (13,063 ) Impact from public subsidiaries dilutive securities (a) — (34,104 ) — — Net earnings (loss) attributable to IAC shareholders $ 272,120 $ 238,016 $ (143,331 ) $ (143,331 ) Denominator: Weighted average basic shares outstanding 79,369 79,369 80,357 80,357 Dilutive securities including stock options and RSUs and subsidiary denominated equity awards (b)(c)(d)(e) — 5,133 — — Denominator for earnings per share—weighted average shares (b)(c)(d)(e) 79,369 84,502 80,357 80,357 Earnings (loss) per share attributable to IAC shareholders: Earnings (loss) per share $ 3.43 $ 2.82 $ (1.78 ) $ (1.78 ) ________________________ (a) The amount for the three and nine months ended September 30, 2017 and for the three months ended September 30, 2016 reflects the reduction in Match Group's earnings attributable to IAC from the assumed exercise of Match Group dilutive securities under the if-converted method. For the nine months ended September 30, 2016 , the impact on earnings related to Match Group's dilutive securities under the if-converted method is excluded because it would have been anti-dilutive due to the Company's net loss. (b) Dilutive securities for the three and nine months ended September 30, 2017 , includes the impact from the assumed exercise of ANGI Homeservices dilutive securities under the if-converted method, as it is more dilutive for IAC to settle certain ANGI Homeservices equity awards. The impact on earnings of ANGI Homeservices dilutive securities is not applicable for priors prior to the Combination. (c) If the effect is dilutive, weighted average common shares outstanding include the incremental shares that would be issued upon the assumed exercise of stock options and subsidiary denominated equity and vesting of restricted stock units ("RSUs"). For the three months ended September 30, 2017 , there were no potentially dilutive securities excluded from the calculation of diluted earnings per share. For the nine months ended September 30, 2017 and three months ended September 30, 2016 , less than 0.1 million and 3.3 million potentially dilutive securities, respectively, are excluded from the calculation of diluted earnings per share because their inclusion would have been anti-dilutive. (d) For the nine months ended September 30, 2016 , the Company had a loss from operations and, as a result, approximately 9.8 million potentially dilutive securities were excluded from computing diluted earnings per share because the impact would have been anti-dilutive. Accordingly, the weighted average basic shares outstanding were used to compute the diluted earnings per share amount. (e) Market-based awards and performance-based stock units (“PSUs”) are considered contingently issuable shares. Shares issuable upon exercise or vesting of market-based awards and PSUs are included in the denominator for earnings per share if (i) the applicable market or performance condition(s) has been met and (ii) the inclusion of the market-based awards and PSUs is dilutive for the respective reporting periods. For the three and nine months ended September 30, 2017 and three months ended September 30, 2016 , 0.3 million shares underlying market-based awards and PSUs were excluded from the calculation of diluted earnings per share because the market or performance conditions had not been met.

SEGMENT INFORMATION

SEGMENT INFORMATION	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
SEGMENT INFORMATION	SEGMENT INFORMATION The overall concept that IAC employs in determining its operating segments is to present the financial information in a manner consistent with: how the chief operating decision maker views the businesses; how the businesses are organized as to segment management; and the focus of the businesses with regards to the types of services or products offered or the target market. Operating segments are combined for reporting purposes if they meet certain aggregation criteria, which principally relate to the similarity of their economic characteristics or, in the case of the Other reportable segment, do not meet the quantitative thresholds that require presentation as separate reportable segments. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Revenue: Match Group $ 343,418 $ 287,530 $ 951,754 $ 823,240 ANGI Homeservices 181,717 133,560 513,173 375,222 Video 78,338 59,955 184,097 162,361 Applications 136,333 142,782 439,199 445,735 Publishing 88,755 74,902 244,959 326,195 Other (a) — 65,515 23,980 196,323 Inter-segment eliminations (127 ) (142 ) (508 ) (356 ) Total $ 828,434 $ 764,102 $ 2,356,654 $ 2,328,720 ___________________ (a) The Other segment consists of the results of PriceRunner, ShoeBuy and The Princeton Review for periods prior to the sale of these businesses, which occurred on March 18, 2016, December 30, 2016 and March 31, 2017, respectively. Beginning in the second quarter of 2017, as a result of the sale of these businesses, the Other segment does not include any financial results. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Operating Income (Loss): Match Group $ 91,008 $ 90,938 $ 232,854 $ 202,624 ANGI Homeservices (112,505 ) 10,148 (115,258 ) 19,147 Video (1,809 ) (2,663 ) (25,227 ) (25,187 ) Applications 29,386 29,240 101,288 75,839 Publishing 5,677 (14,562 ) (2,968 ) (324,720 ) Other — (695 ) (5,621 ) (11,313 ) Corporate (30,346 ) (26,822 ) (90,962 ) (81,835 ) Total $ (18,589 ) $ 85,584 $ 94,106 $ (145,445 ) Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Adjusted EBITDA: (b) Match Group $ 119,564 $ 107,101 $ 315,705 $ 275,834 ANGI Homeservices (2,266 ) 15,291 21,612 33,927 Video (822 ) (894 ) (22,386 ) (21,770 ) Applications 31,077 34,575 106,556 94,715 Publishing 7,088 (6,208 ) 11,007 (6,639 ) Other — 2,783 (1,532 ) (1,129 ) Corporate (17,070 ) (13,662 ) (46,908 ) (38,030 ) Total $ 137,571 $ 138,986 $ 384,054 $ 336,908 ________________________ (b) The Company's primary financial measure is Adjusted EBITDA, which is defined as operating income excluding: (1) stock-based compensation expense; (2) depreciation; and (3) acquisition-related items consisting of (i) amortization of intangible assets and impairments of goodwill and intangible assets, if applicable, and (ii) gains and losses recognized on changes in the fair value of contingent consideration arrangements. The Company believes this measure is useful for analysts and investors as this measure allows a more meaningful comparison between our performance and that of our competitors. Moreover, our management uses this measure internally to evaluate the performance of our business as a whole and our individual business segments, and this measure is one of the primary metrics by which our internal budgets are based and by which management is compensated. The above items are excluded from our Adjusted EBITDA measure because these items are non-cash in nature, and we believe that by excluding these items, Adjusted EBITDA corresponds more closely to the cash operating income generated from our business, from which capital investments are made and debt is serviced. Adjusted EBITDA has certain limitations in that it does not take into account the impact to IAC's statement of operations of certain expenses. The following table presents the revenue of the Company's principal segments disaggregated by type of service: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Match Group Direct revenue $ 330,098 $ 273,727 $ 917,273 $ 786,176 Indirect revenue (principally advertising revenue) 13,320 13,803 34,481 37,064 Total Match Group revenue $ 343,418 $ 287,530 $ 951,754 $ 823,240 ANGI Homeservices Consumer connection revenue (c) $ 151,056 $ 110,874 $ 427,854 $ 310,962 Membership subscription revenue 22,146 14,083 61,145 40,008 Other 8,515 8,603 24,174 24,252 Total ANGI Homeservices revenue $ 181,717 $ 133,560 $ 513,173 $ 375,222 Applications Advertising $ 121,425 $ 129,027 $ 390,160 $ 409,212 Subscription (including downloadable app fees) and other 14,908 13,755 49,039 36,523 Total Applications revenue $ 136,333 $ 142,782 $ 439,199 $ 445,735 Publishing Advertising $ 87,788 $ 74,272 $ 242,957 $ 324,422 Other 967 630 2,002 1,773 Total Publishing revenue $ 88,755 $ 74,902 $ 244,959 $ 326,195 ___________________ (c) Fees paid by service professionals for consumer matches. Revenue by geography is based on where the customer is located. Geographic information about revenue and long-lived assets is presented below: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Revenue: United States $ 577,362 $ 567,132 $ 1,670,980 $ 1,721,348 All other countries 251,072 196,970 685,674 607,372 Total $ 828,434 $ 764,102 $ 2,356,654 $ 2,328,720 September 30, December 31, (In thousands) Long-lived assets (excluding goodwill and intangible assets): United States $ 293,005 $ 281,725 All other countries 27,272 24,523 Total $ 320,277 $ 306,248 The following tables reconcile operating income (loss) for the Company's reportable segments and net earnings (loss) attributable to IAC shareholders to Adjusted EBITDA: Three Months Ended September 30, 2017 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Adjusted EBITDA (In thousands) Match Group $ 91,008 $ 19,949 $ 8,147 $ 401 $ 59 $ 119,564 ANGI Homeservices (112,505 ) 103,980 3,491 2,768 — (2,266 ) Video (1,809 ) 134 541 312 — (822 ) Applications 29,386 — 1,155 536 — 31,077 Publishing 5,677 — 1,062 349 — 7,088 Other — — — — — — Corporate (30,346 ) 10,409 2,867 — — (17,070 ) Total (18,589 ) $ 134,472 $ 17,263 $ 4,366 $ 59 $ 137,571 Interest expense (25,036 ) Other expense, net (10,216 ) Loss before income taxes (53,841 ) Income tax benefit 279,480 Net earnings 225,639 Net earnings attributable to noncontrolling interests (45,996 ) Net earnings attributable to IAC shareholders $ 179,643 Three Months Ended September 30, 2016 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Adjusted EBITDA (In thousands) Match Group $ 90,938 $ 10,718 $ 7,192 $ 3,382 $ (5,129 ) $ 107,101 ANGI Homeservices 10,148 2,391 2,026 726 — 15,291 Video (2,663 ) 640 438 691 — (894 ) Applications 29,240 — 1,073 1,519 2,743 34,575 Publishing (14,562 ) — 2,029 6,325 — (6,208 ) Other (695 ) 427 1,518 1,624 (91 ) 2,783 Corporate (26,822 ) 9,485 3,675 — — (13,662 ) Total 85,584 $ 23,661 $ 17,951 $ 14,267 $ (2,477 ) $ 138,986 Interest expense (27,118 ) Other income, net 11,700 Earnings before income taxes 70,166 Income tax provision (17,826 ) Net earnings 52,340 Net earnings attributable to noncontrolling interests (9,178 ) Net earnings attributable to IAC shareholders $ 43,162 Nine Months Ended September 30, 2017 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Adjusted EBITDA (In thousands) Match Group $ 232,854 $ 53,627 $ 23,619 $ 1,208 $ 4,397 $ 315,705 ANGI Homeservices (115,258 ) 120,280 9,705 6,885 — 21,612 Video (25,227 ) 267 1,637 937 — (22,386 ) Applications 101,288 — 3,087 1,633 548 106,556 Publishing (2,968 ) — 4,011 9,964 — 11,007 Other (5,621 ) 1,729 836 1,524 — (1,532 ) Corporate (90,962 ) 31,459 12,595 — — (46,908 ) Total 94,106 $ 207,362 $ 55,490 $ 22,151 $ 4,945 $ 384,054 Interest expense (74,556 ) Other expense, net (7,700 ) Earnings before income taxes 11,850 Income tax benefit 322,809 Net earnings 334,659 Net earnings attributable to noncontrolling interests (62,539 ) Net earnings attributable to IAC shareholders $ 272,120 Nine Months Ended September 30, 2016 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Goodwill Impairment Adjusted EBITDA (In thousands) Match Group $ 202,624 $ 40,810 $ 20,119 $ 15,004 $ (2,723 ) $ — $ 275,834 ANGI Homeservices 19,147 6,685 5,824 2,271 — — 33,927 Video (25,187 ) 640 1,313 1,656 (192 ) — (21,770 ) Applications 75,839 — 3,304 4,573 10,999 — 94,715 Publishing (324,720 ) — 6,366 36,348 — 275,367 (6,639 ) Other (11,313 ) 531 4,534 5,210 (91 ) — (1,129 ) Corporate (81,835 ) 33,944 9,861 — — — (38,030 ) Total (145,445 ) $ 82,610 $ 51,321 $ 65,062 $ 7,993 $ 275,367 $ 336,908 Interest expense (82,622 ) Other income, net 20,405 Loss before income taxes (207,662 ) Income tax benefit 77,394 Net loss (130,268 ) Net earnings attributable to noncontrolling interests (13,063 ) Net loss attributable to IAC shareholders $ (143,331 )

CONSOLIDATED FINANCIAL STATEMEN

CONSOLIDATED FINANCIAL STATEMENT DETAILS	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
CONSOLIDATED FINANCIAL STATEMENT DETAILS	CONSOLIDATED FINANCIAL STATEMENT DETAILS Other (expense) income, net consists of: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Other (expense) income, net $ (10,216 ) $ 11,700 $ (7,700 ) $ 20,405 Three months ended September 30, 2017 and 2016 Other expense, net in 2017 includes $10.2 million in net foreign currency exchange losses due primarily to the weakening of the dollar relative to the British Pound and Euro, $2.9 million in other-than-temporary impairment charges related to certain cost method investments as a result of our assessment of the near-term prospects and financial condition of the investees, an expense of $2.1 million related to the repricing of the Match Group Term Loan and an expense of $1.5 million related to a mark-to-market adjustment pertaining to a subsidiary denominated equity award held by a non-employee, partially offset by $4.5 million in gains related to the sales of certain investments and interest income of $2.9 million . Other income, net in 2016 primarily includes $10.9 million in net foreign currency exchange gains due primarily to the strengthening of the dollar relative to the British Pound and Euro, interest income of $1.1 million and income of $0.9 million related to a mark-to-market adjustment pertaining to a subsidiary denominated equity award held by a non-employee, partially offset by $1.8 million in other-than-temporary impairment charges related to certain cost method investments. Nine months ended September 30, 2017 and 2016 Other expense, net in 2017 includes $16.3 million in net foreign currency exchange losses due primarily to the weakening of the dollar relative to the British Pound and Euro, an expense of $12.2 million related to a mark-to-market adjustment pertaining to a subsidiary denominated equity award held by a non-employee, $7.7 million in other-than-temporary impairment charges related to certain cost method investments as a result of our assessment of the near-term prospects and financial condition of the investees, an expense of $2.1 million related to the repricing of the Match Group Term Loan and a loss of $1.2 million related to the sale of The Princeton Review, partially offset by $25.8 million in gains related to the sales of certain investments and interest income of $7.1 million . Other income, net in 2016 includes $24.0 million in net foreign currency exchange gains, a $12.0 million gain related to the sale of PriceRunner, interest income of $3.8 million and a $3.5 million gain related to the sale of marketable equity securities, partially offset by a non-cash charge of $11.1 million related to the write-off of a proportionate share of original issue discount and deferred financing costs associated with the repayment of $400 million of the Match Group Term Loan, $4.5 million in other-than-temporary impairment charges related to certain cost method investments, a loss of $3.8 million related to the sale of ASKfm, a $3.2 million loss on the 4.75% and 4.875% Senior Note redemptions and repurchases and an expense of $2.5 million related to a mark-to-market adjustment pertaining to a subsidiary denominated equity award held by a non-employee.

CONTINGENCIES

CONTINGENCIES	9 Months Ended
	Sep. 30, 2017
Loss Contingency [Abstract]
CONTINGENCIES	CONTINGENCIES In the ordinary course of business, the Company is a party to various lawsuits. The Company establishes reserves for specific legal matters when it determines that the likelihood of an unfavorable outcome is probable and the loss is reasonably estimable. Management has also identified certain other legal matters where we believe an unfavorable outcome is not probable and, therefore, no reserve is established. Although management currently believes that resolving claims against us, including claims where an unfavorable outcome is reasonably possible, will not have a material impact on the liquidity, results of operations, or financial condition of the Company, these matters are subject to inherent uncertainties and management's view of these matters may change in the future. The Company also evaluates other contingent matters, including income and non-income tax contingencies, to assess the likelihood of an unfavorable outcome and estimated extent of potential loss. It is possible that an unfavorable outcome of one or more of these lawsuits or other contingencies could have a material impact on the liquidity, results of operations, or financial condition of the Company. See " Note 2—Income Taxes " for additional information related to income tax contingencies.

RELATED PARTY TRANSACTION

RELATED PARTY TRANSACTION	9 Months Ended
	Sep. 30, 2017
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTION	RELATED PARTY TRANSACTIONS WITH ANGI HOMESERVICES IAC and ANGI Homeservices, in connection with the Combination, entered into the following agreements: • A Contribution Agreement under which the Company separated its HomeAdvisor business from its other businesses and caused the HomeAdvisor business to be transferred to ANGI Homeservices prior to the Combination. Under the Contribution Agreement, ANGI Homeservices agrees to indemnify IAC against any losses arising out of any breach by ANGI Homeservices of the Contribution Agreement; • An Investor Rights Agreement that provides IAC with (i) specified registration and other rights relating to shares of ANGI Homeservices' common stock owned by IAC; (ii) anti-dilution rights with respect to ANGI Homeservices' common stock; and (iii) specified board matters with respect to designation of ANGI Homeservices directors; • A Services Agreement, under which IAC has agreed to provide a range of services to ANGI Homeservices, including, among others, (i) assistance with certain legal, M&A, human resources, finance, risk management, internal audit and treasury functions, health and wellness, information security services and insurance and tax affairs, including assistance with certain public company and unclaimed property reporting obligations; (ii) accounting, controllership and payroll processing services; (iii) investor relations services; (iv) tax compliance services; and (iv) such other services as to which IAC and ANGI Homeservices may agree. • A Tax Sharing Agreement, which governs the respective rights, responsibilities and obligations of IAC and ANGI Homeservices with respect to tax matters, including taxes attributable to ANGI Homeservices, entitlement to refunds, allocation of tax attributes, preparation of tax returns, certain tax elections, control of tax contests and other tax matters regarding U.S. federal, state, local and foreign income taxes; and • An Employee Matters Agreement, which governs the respective rights, responsibilities and obligations of IAC and ANGI Homeservices after the closing of the merger w ith respect to a range of compensation and benefit issues. Additionally, on September 29, 2017, IAC issued two intercompany notes (collectively referred to as "Intercompany Notes") to ANGI Homeservices as follows: (i) a Payoff Intercompany Note, which provided the funds necessary to repay the outstanding balance under Angie's List's previously existing credit agreement, totaling approximately $61.5 million ; and (ii) a Working Capital Intercompany Note, which provided ANGI Homeservices with $15 million for working capital purposes. The Intercompany Notes eliminate in the Company's accompanying consolidated balance sheet. These Intercompany Notes were repaid on November 1, 2017, with a portion of the proceeds from the Term Loan that were received on the same date. See " Note 14—Subsequent Events " for further information.

GUARANTOR AND NON-GUARANTOR FIN

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION	9 Months Ended
	Sep. 30, 2017
Guarantor and Nonguarantor Financial Statements [Abstract]
GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION	GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION The 4.875% and 4.75% Senior Notes are unconditionally guaranteed, jointly and severally, by certain domestic subsidiaries which are 100% owned by the Company. The following tables present condensed consolidating financial information at September 30, 2017 and December 31, 2016 and for the three and nine months ended September 30, 2017 and 2016 for: IAC, on a stand-alone basis; the combined guarantor subsidiaries of IAC; the combined non-guarantor subsidiaries of IAC; and IAC on a consolidated basis. Balance sheet at September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Cash and cash equivalents $ 501,918 $ — $ 753,399 $ — $ 1,255,317 Accounts receivable, net — 81,448 189,761 — 271,209 Other current assets 59,319 21,305 119,753 — 200,377 Intercompany receivables — 754,376 1,280,777 (2,035,153 ) — Property and equipment, net 3,163 160,968 156,146 — 320,277 Goodwill — 412,010 2,089,579 — 2,501,589 Intangible assets, net — 75,627 584,476 — 660,103 Investment in subsidiaries 4,489,006 549,342 — (5,038,348 ) — Other non-current assets 50,991 115,668 356,853 (191,429 ) 332,083 Total assets $ 5,104,397 $ 2,170,744 $ 5,530,744 $ (7,264,930 ) $ 5,540,955 Accounts payable $ 2,521 $ 23,806 $ 78,479 $ — $ 104,806 Other current liabilities 50,523 69,445 610,752 — 730,720 Long-term debt, net of current portion 395,269 — 1,253,998 — 1,649,267 Income taxes payable 11 3,270 30,009 — 33,290 Intercompany liabilities 2,035,153 — — (2,035,153 ) — Other long-term liabilities 191,999 18,741 53,877 (191,429 ) 73,188 Redeemable noncontrolling interests — — 40,981 — 40,981 IAC shareholders' equity 2,428,921 2,055,482 2,982,866 (5,038,348 ) 2,428,921 Noncontrolling interests — — 479,782 — 479,782 Total liabilities and shareholders' equity $ 5,104,397 $ 2,170,744 $ 5,530,744 $ (7,264,930 ) $ 5,540,955 Balance sheet at December 31, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Cash and cash equivalents $ 553,643 $ — $ 775,544 $ — $ 1,329,187 Marketable securities 89,342 — — — 89,342 Accounts receivable, net — 77,335 142,803 — 220,138 Other current assets 71,152 36,154 96,762 — 204,068 Intercompany receivables — 650,595 1,123,925 (1,774,520 ) — Property and equipment, net 4,350 159,304 142,594 — 306,248 Goodwill — 412,010 1,512,042 — 1,924,052 Intangible assets, net — 83,179 272,272 — 355,451 Investment in subsidiaries 3,659,570 523,814 — (4,183,384 ) — Other non-current assets 52,228 115,150 165,482 (115,473 ) 217,387 Total assets $ 4,430,285 $ 2,057,541 $ 4,231,424 $ (6,073,377 ) $ 4,645,873 Current portion of long-term debt $ 20,000 $ — $ — $ — $ 20,000 Accounts payable 2,697 29,867 30,299 — 62,863 Other current liabilities 42,441 84,629 503,455 — 630,525 Long-term debt, net of current portion 405,991 — 1,176,493 — 1,582,484 Income taxes payable — 3,470 30,274 (216 ) 33,528 Intercompany liabilities 1,774,520 — — (1,774,520 ) — Other long-term liabilities 315,414 20,952 51,867 (115,257 ) 272,976 Redeemable noncontrolling interests — — 32,827 — 32,827 IAC shareholders' equity 1,869,222 1,918,623 2,264,761 (4,183,384 ) 1,869,222 Noncontrolling interests — — 141,448 — 141,448 Total liabilities and shareholders' equity $ 4,430,285 $ 2,057,541 $ 4,231,424 $ (6,073,377 ) $ 4,645,873 Statement of operations for the three months ended September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 185,386 $ 643,175 $ (127 ) $ 828,434 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) — 41,741 124,676 (127 ) 166,290 Selling and marketing expense 312 84,416 268,181 (30 ) 352,879 General and administrative expense 32,060 15,676 187,814 30 235,580 Product development expense 593 13,145 56,907 — 70,645 Depreciation 406 3,822 13,035 — 17,263 Amortization of intangibles — 350 4,016 — 4,366 Total operating costs and expenses 33,371 159,150 654,629 (127 ) 847,023 Operating (loss) income (33,371 ) 26,236 (11,454 ) — (18,589 ) Equity in earnings of unconsolidated affiliates 203,808 4,229 — (208,037 ) — Interest expense (5,483 ) — (19,553 ) — (25,036 ) Other (expense) income, net (8,157 ) 8,311 (10,370 ) — (10,216 ) Earnings (loss) before income taxes 156,797 38,776 (41,377 ) (208,037 ) (53,841 ) Income tax benefit (provision) 22,846 (11,710 ) 268,344 — 279,480 Net earnings 179,643 27,066 226,967 (208,037 ) 225,639 Net earnings attributable to noncontrolling interests — — (45,996 ) — (45,996 ) Net earnings attributable to IAC shareholders $ 179,643 $ 27,066 $ 180,971 $ (208,037 ) $ 179,643 Comprehensive income attributable to IAC shareholders $ 216,868 $ 26,789 $ 224,929 $ (251,718 ) $ 216,868 Statement of operations for the three months ended September 30, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 206,107 $ 558,154 $ (159 ) $ 764,102 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) 219 63,730 115,226 (44 ) 179,131 Selling and marketing expense 546 87,051 205,620 (221 ) 292,996 General and administrative expense 22,375 20,243 81,745 106 124,469 Product development expense 1,009 16,453 32,242 — 49,704 Depreciation 422 6,051 11,478 — 17,951 Amortization of intangibles — 6,100 8,167 — 14,267 Total operating costs and expenses 24,571 199,628 454,478 (159 ) 678,518 Operating (loss) income (24,571 ) 6,479 103,676 — 85,584 Equity in earnings (losses) of unconsolidated affiliates 71,471 (22,707 ) — (48,764 ) — Interest expense (6,362 ) — (20,756 ) — (27,118 ) Other (expense) income, net (6,334 ) 4,837 13,197 — 11,700 Earnings (loss) before income taxes 34,204 (11,391 ) 96,117 (48,764 ) 70,166 Income tax benefit (provision) 8,958 (4,263 ) (22,521 ) — (17,826 ) Net earnings (loss) 43,162 (15,654 ) 73,596 (48,764 ) 52,340 Net earnings attributable to noncontrolling interests — — (9,178 ) — (9,178 ) Net earnings (loss) attributable to IAC shareholders $ 43,162 $ (15,654 ) $ 64,418 $ (48,764 ) $ 43,162 Comprehensive income (loss) attributable to IAC shareholders $ 37,885 $ (15,605 ) $ 59,542 $ (43,937 ) $ 37,885 Statement of operations for the nine months ended September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 536,789 $ 1,820,373 $ (508 ) $ 2,356,654 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) 159 104,581 346,975 (434 ) 451,281 Selling and marketing expense 1,250 258,634 763,640 (130 ) 1,023,394 General and administrative expense 93,974 46,777 388,590 56 529,397 Product development expense 2,098 42,324 136,413 — 180,835 Depreciation 1,290 15,799 38,401 — 55,490 Amortization of intangibles — 10,102 12,049 — 22,151 Total operating costs and expenses 98,771 478,217 1,686,068 (508 ) 2,262,548 Operating (loss) income (98,771 ) 58,572 134,305 — 94,106 Equity in earnings of unconsolidated affiliates 346,643 8,170 — (354,813 ) — Interest expense (16,960 ) — (57,596 ) — (74,556 ) Other (expense) income, net (20,783 ) 21,207 (8,124 ) — (7,700 ) Earnings before income taxes 210,129 87,949 68,585 (354,813 ) 11,850 Income tax benefit (provision) 61,991 (22,651 ) 283,469 — 322,809 Net earnings 272,120 65,298 352,054 (354,813 ) 334,659 Net earnings attributable to noncontrolling interests — — (62,539 ) — (62,539 ) Net earnings attributable to IAC shareholders $ 272,120 $ 65,298 $ 289,515 $ (354,813 ) $ 272,120 Comprehensive income attributable to IAC shareholders $ 338,730 $ 67,276 $ 373,635 $ (440,911 ) $ 338,730 Statement of operations for the nine months ended September 30, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 710,915 $ 1,618,178 $ (373 ) $ 2,328,720 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) 811 201,326 341,346 (221 ) 543,262 Selling and marketing expense 2,306 323,681 646,777 (274 ) 972,490 General and administrative expense 66,208 65,491 272,475 122 404,296 Product development expense 4,127 55,334 102,906 — 162,367 Depreciation 1,274 17,144 32,903 — 51,321 Amortization of intangibles — 35,183 29,879 — 65,062 Goodwill impairment — 253,245 22,122 — 275,367 Total operating costs and expenses 74,726 951,404 1,448,408 (373 ) 2,474,165 Operating (loss) income (74,726 ) (240,489 ) 169,770 — (145,445 ) Equity in losses of unconsolidated affiliates (44,988 ) (29,893 ) — 74,881 — Interest expense (20,776 ) — (61,846 ) — (82,622 ) Other (expense) income, net (35,306 ) 11,251 44,460 — 20,405 (Loss) earnings before income taxes (175,796 ) (259,131 ) 152,384 74,881 (207,662 ) Income tax benefit (provision) 32,465 81,742 (36,813 ) — 77,394 Net (loss) earnings (143,331 ) (177,389 ) 115,571 74,881 (130,268 ) Net earnings attributable to noncontrolling interests — — (13,063 ) — (13,063 ) Net (loss) earnings attributable to IAC shareholders $ (143,331 ) $ (177,389 ) $ 102,508 $ 74,881 $ (143,331 ) Comprehensive (loss) income attributable to IAC shareholders $ (135,043 ) $ (157,069 ) $ 108,007 $ 49,062 $ (135,043 ) Statement of cash flows for the nine months ended September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Net cash (used in) provided by operating activities $ (35,286 ) $ 76,616 $ 256,267 $ — $ 297,597 Cash flows from investing activities: Acquisitions, net of cash acquired — (2,200 ) (66,913 ) — (69,113 ) Capital expenditures (337 ) (17,263 ) (38,919 ) — (56,519 ) Proceeds from maturities and sales of marketable debt securities 114,350 — — — 114,350 Purchases of marketable debt securities (24,909 ) — — — (24,909 ) Purchases of investments — — (9,105 ) — (9,105 ) Net proceeds from the sale of businesses and investments 911 — 124,309 — 125,220 Intercompany (108,258 ) — — 108,258 — Other, net — 307 1,012 — 1,319 Net cash (used in) provided by investing activities (18,243 ) (19,156 ) 10,384 108,258 81,243 Cash flows from financing activities: Purchase of IAC treasury stock (56,424 ) — — — (56,424 ) Proceeds from Match Group Term Loan — — 75,000 — 75,000 Debt issuance costs — — (2,637 ) — (2,637 ) Repurchases of IAC Senior Notes (31,590 ) — — — (31,590 ) Proceeds from the exercise of IAC stock options 69,065 — — — 69,065 Withholding taxes paid on behalf of IAC net settled stock-based awards (57,180 ) — — — (57,180 ) Proceeds from the exercise of Match Group stock options — — 57,705 — 57,705 Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards — — (501,437 ) — (501,437 ) Purchase of noncontrolling interests — — (13,011 ) — (13,011 ) Acquisition-related contingent consideration payments — — (27,289 ) — (27,289 ) Funds returned from escrow for MyHammer tender offer — — 10,604 — 10,604 Decrease in restricted cash related to bond redemptions 20,141 — — 20,141 Intercompany 57,460 (57,460 ) 108,258 (108,258 ) — Other, net 251 — (5,253 ) — (5,002 ) Net cash provided by (used in) financing activities 1,723 (57,460 ) (298,060 ) (108,258 ) (462,055 ) Total cash used (51,806 ) — (31,409 ) — (83,215 ) Effect of exchange rate changes on cash and cash equivalents 81 — 9,264 — 9,345 Net decrease in cash and cash equivalents (51,725 ) — (22,145 ) — (73,870 ) Cash and cash equivalents at beginning of period 553,643 — 775,544 — 1,329,187 Cash and cash equivalents at end of period $ 501,918 $ — $ 753,399 $ — $ 1,255,317 Statement of cash flows for the nine months ended September 30, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Net cash (used in) provided by operating activities $ (60,394 ) $ 66,421 $ 188,232 $ — $ 194,259 Cash flows from investing activities: Acquisitions, net of cash acquired — — (2,524 ) — (2,524 ) Capital expenditures (343 ) (4,747 ) (57,649 ) — (62,739 ) Investments in time deposits — — (87,500 ) — (87,500 ) Proceeds from maturities of time deposits — — 87,500 — 87,500 Proceeds from maturities and sales of marketable debt securities 79,210 — — — 79,210 Purchases of marketable debt securities (229,246 ) — — — (229,246 ) Purchases of investments — — (7,211 ) — (7,211 ) Net proceeds from the sale of businesses and investments 15,401 1,779 93,356 — 110,536 Intercompany (58,998 ) — — 58,998 — Other, net — 158 5,404 — 5,562 Net cash (used in) provided by investing activities (193,976 ) (2,810 ) 31,376 58,998 (106,412 ) Cash flows from financing activities: Purchase of IAC treasury stock (247,256 ) — — — (247,256 ) Proceeds from Match Group 6.375% Senior Notes offering — — 400,000 — 400,000 Principal payment on Match Group Term Loan — — (410,000 ) — (410,000 ) Debt issuance costs — — (5,048 ) — (5,048 ) Repurchases of IAC Senior Notes (126,271 ) — — — (126,271 ) Proceeds from the exercise of IAC stock options 19,536 — — — 19,536 Withholding taxes paid on behalf of IAC net settled stock-based awards (26,684 ) — — — (26,684 ) Proceeds from the exercise of Match Group stock options — — 30,246 — 30,246 Withholding taxes paid on behalf of Match Group net settled stock-based awards — — (29,779 ) — (29,779 ) Purchase of noncontrolling interests (1,400 ) — (1,129 ) — (2,529 ) Acquisition-related contingent consideration payments — (351 ) (1,829 ) — (2,180 ) Decrease in restricted cash related to bond redemptions 20,000 — — — 20,000 Intercompany 63,261 (63,260 ) 58,997 (58,998 ) — Other, net — — (766 ) — (766 ) Net cash (used in) provided by financing activities (298,814 ) (63,611 ) 40,692 (58,998 ) (380,731 ) Total cash (used) provided (553,184 ) — 260,300 — (292,884 ) Effect of exchange rate changes on cash and cash equivalents — — 1,221 — 1,221 Net (decrease) increase in cash and cash equivalents (553,184 ) — 261,521 — (291,663 ) Cash and cash equivalents at beginning of period 1,074,658 — 406,789 — 1,481,447 Cash and cash equivalents at end of period $ 521,474 $ — $ 668,310 $ — $ 1,189,784

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS On October 2, 2017, IAC FinanceCo, Inc., a direct, wholly-owned subsidiary of the Company, completed a private offering of $517.5 million aggregate principal amount of its 0.875% Exchangeable Senior Notes due October 1, 2022 (the “0.875% Exchangeable Senior Notes”), with interest payable each April 1 and October 1, commencing on April 1, 2018. The 0.875% Exchangeable Senior Notes are guaranteed by the Company. The net proceeds from the sale of the 0.875% Exchangeable Senior Notes were approximately $500.5 million , after deducting fees and expenses. The net proceeds from the offering were used to: • pay the net premium of approximately $50.7 million on the exchangeable note hedge and warrant transactions; and • loaned to IAC, which repaid the outstanding balance of the 4.875% Senior Notes of $361.9 million , plus accrued interest of $8.8 million . The 4.875% Senior Notes were called for redemption on October 2, 2017 and will be redeemed and canceled on November 30, 2017. In connection with the call for redemption, the Company satisfied and discharged that certain Indenture, dated as of November 15, 2013, by and among the Company, as issuer, the guarantors named therein and Computershare Trust Company, N.A., as trustee, relating to the 4.875% Senior Notes. The exchange rate for the 0.875% Exchangeable Senior Notes is initially 6.5713 shares of the Company's common stock per $1,000 principal amount of the notes, which is equivalent to an initial exchange price of $152.18 per share of the Company's common stock. In connection with this debt offering, the Company purchased call options at $152.18 per share, covering the entire 3.4 million shares that would be issuable upon the conversion of the notes, and sold warrants for 3.4 million shares at $229.70 per share. The exchangeable note hedge transactions are expected to reduce the potential dilutive effect of the Company's common stock upon any exchange of notes and/or offset any cash payment IAC FinanceCo, Inc. is required to make in excess of the principal amount of the exchanged notes. The warrants could separately have a dilutive effect on the Company's common stock to the extent that the market price per share of the Company common stock (as measured over the measurement period at the maturity of the warrants) exceeds the applicable strike price of the warrants. On October 2, 2017, IAC Group, LLC, a wholly-owned subsidiary of the Company, entered into a joinder agreement by and among IAC Group, the Company, and each of the other loan parties party to the IAC Credit Facility. Pursuant to the joinder agreement, IAC Group became the successor borrower under the IAC Credit Facility and IAC's obligations under the credit agreement were terminated. On October 23, 2017, the Company, through Match Group, sold its largest cost method investment, Zhenai Inc., a leading provider of online dating and matchmaking services in China. The net proceeds from the sale were $60.2 million . On November 1, 2017, ANGI Homeservices entered into a credit agreement which provides for a five -year term loan A facility of $275 million ("ANGI Homeservices Term Loan"). The ANGI Homeservices Term Loan is guaranteed by ANGI Homeservices' wholly-owned material domestic subsidiaries and is secured by substantially all assets of ANGI Homeservices and the guarantors, subject to certain exceptions. The ANGI Homeservices Term Loan currently bears interest at LIBOR plus 200 basis points , which is subject to change based on the borrower's consolidated net leverage ratio. Interest payments are due at least quarterly through the term of the loan. The ANGI Homeservices Term Loan also requires quarterly amortization payments of 1.25% of the original principal amount thereof in the first three years, 2.5% in the fourth year and 3.75% thereafter. A portion of the proceeds of the loan were used to repay the Intercompany Notes and the remaining proceeds will be used for general corporate purposes. See " Note 12—Related Party Transactions with ANGI Homeservices " for further information on the Intercompany Notes outstanding between ANGI Homeservices and the Company.

THE COMPANY AND SUMMARY OF SI24

THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The Company prepares its consolidated financial statements in accordance with U.S. generally accepted accounting principles ("GAAP").
Basis of Consolidation and Accounting for Investments	Basis of Consolidation and Accounting for Investments The consolidated financial statements include the accounts of the Company, all entities that are wholly-owned by the Company and all entities in which the Company has a controlling financial interest. Intercompany transactions and accounts have been eliminated. Investments in the common stock or in-substance common stock of entities in which the Company has the ability to exercise significant influence over the operating and financial matters of the investee, but does not have a controlling financial interest, are accounted for using the equity method and are included in "Long-term investments" in the accompanying consolidated balance sheet. In management's opinion, the unaudited interim consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and reflect all adjustments, consisting of normal and recurring adjustments, necessary for the fair presentation of our financial position, results of operations and cash flows for the periods presented. Interim results are not necessarily indicative of the results that may be expected for the full year. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company's Current Report on Form 8-K dated July 18, 2017.
Accounting Estimates	Accounting Estimates Management of the Company is required to make certain estimates, judgments and assumptions during the preparation of its consolidated financial statements in accordance with GAAP. These estimates, judgments and assumptions impact the reported amounts of assets, liabilities, revenue and expenses and the related disclosure of contingent assets and liabilities. On an ongoing basis, the Company evaluates its estimates and judgments including those related to: the recoverability of goodwill and indefinite-lived intangible assets; the useful lives and recoverability of definite-lived intangible assets and property and equipment; the fair value of long-term investments; the carrying value of accounts receivable, including the determination of the allowance for doubtful accounts; the determination of revenue reserves; the fair value of acquisition-related contingent consideration arrangements; the liabilities for uncertain tax positions; the valuation allowance for deferred income tax assets; and the fair value of and forfeiture rates for stock-based awards, among others. The Company bases its estimates and judgments on historical experience, its forecasts and budgets and other factors that the Company considers relevant. Actual results could differ from these estimates.
Certain Risks and Concentrations	Certain Risks and Concentrations A meaningful portion of the Company's revenue is derived from online advertising, the market for which is highly competitive and rapidly changing. Significant changes in this industry or changes in advertising spending behavior or in customer buying behavior could adversely affect our operating results. Most of the Company's online advertising revenue is attributable to a services agreement with Google Inc. ("Google"). For the three and nine months ended September 30, 2017 , revenue from Google represents 21% and 23% , respectively, of the Company's consolidated revenue. For the three and nine months ended September 30, 2016 , revenue from Google represents 23% and 27% , respectively, of the Company's consolidated revenue. The services agreement became effective on April 1, 2016, following the expiration of the previous services agreement, and expires on March 31, 2020; however, the Company may choose to terminate the agreement effective March 31, 2019. The services agreement requires that the Company comply with certain guidelines promulgated by Google. Google may generally unilaterally update its policies and guidelines without advance notice, which could in turn require modifications to, or prohibit and/or render obsolete certain of our products, services and/or business practices, which could be costly to address or otherwise have an adverse effect on our business, financial condition and results of operations.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Accounting Pronouncements not yet adopted by the Company In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers, which clarifies the principles for recognizing revenue and develops a common standard for all industries. ASU No. 2014-09 was subsequently amended during 2015, 2016 and 2017; these amendments provide further revenue recognition guidance related to principal versus agent considerations, performance obligations and licensing, narrow-scope improvements and practical expedients. ASU No. 2014-09 is a comprehensive revenue recognition standard that will supersede nearly all existing revenue recognition guidance under GAAP. The new standard provides a single principles-based, five-step model to be applied to all contracts with customers. This five-step model includes (1) identifying the contract(s) with the customer, (2) identifying the performance obligations in the contract, (3) determining the transaction price, (4) allocating the transaction price to the performance obligations in the contract and (5) recognizing revenue when each performance obligation is satisfied. More specifically, revenue will be recognized when promised goods or services are transferred to the customer in an amount that reflects the consideration expected in exchange for those goods or services. ASU No. 2014-09 is effective for interim and annual reporting periods beginning after December 15, 2017, with early adoption permitted for interim and annual reporting periods beginning after December 15, 2016. Upon adoption, ASU No. 2014-09 may either be applied retrospectively to each prior period presented or using the modified retrospective approach with the cumulative effect recognized as of the date of initial application. While the Company’s evaluation of the impact the adoption of ASU No. 2014-09 on its consolidated financial statements continues, it has progressed to the point where we have reached certain preliminary determinations. • The Company will adopt ASU No. 2014-09 using the modified retrospective approach effective January 1, 2018. Therefore, the cumulative effect of adoption will be reflected as an adjustment to beginning retained earnings in the Form 10-Q for the period ending March 31, 2018. • The Company’s assessment of the accounting for mobile app store fees incurred by Match Group in connection with obtaining members is still preliminary and ongoing. Match Group currently capitalizes these costs and amortizes them over the period of the applicable membership periods, which generally range from one to six months. The Company’s initial conclusions in applying ASU No. 2014-09 to these costs were: (1) these costs represent the incremental direct costs of obtaining a membership contract and (2) would, therefore, continue to be capitalized and amortized as incurred. The Company is reassessing this conclusion in light of its finding that there are divergent and evolving interpretations of the correct application of ASU No. 2014-09 to these costs. The total capitalized mobile app store fees were $19.8 million as of September 30, 2017. • Within ANGI Homeservices, the effect of the adoption of ASU No. 2014-09 on HomeAdvisor will be that sales commissions, which represent the incremental direct costs of obtaining a service professional contract, will be capitalized and amortized over the average life of a service professional. These costs are expensed as incurred today. Prior to the Combination, Angie's List capitalized sales commissions and amortized the cost over the term of the applicable advertising contract. Following the Combination, Angie's List accounting policies will be conformed to the Company's accounting policies and these costs will be expensed as incurred. Following the adoption of ASU No. 2014-09, these costs will be capitalized and amortized over the average life of a service professional. • Within Applications, the primary effect of the adoption of ASU No. 2014-09 will be to accelerate the recognition of the portion of the revenue of certain desktop applications sold by SlimWare that qualify as functional intellectual property under ASU No. 2014-09. This revenue is currently deferred and recognized over the applicable subscription term. The Company does not expect the adoption of ASU No. 2014-09 to have a material effect on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) , which supersedes existing guidance on accounting for leases in "Leases (Topic 840)" and generally requires all leases to be recognized in the statement of financial position. The provisions of ASU No. 2016-02 are effective for reporting periods beginning after December 15, 2018; early adoption is permitted. The provisions of ASU No. 2016-02 are to be applied using a modified retrospective approach. The Company will adopt ASU No. 2016-02 effective January 1, 2019. The Company is currently evaluating the impact the adoption of this standard update will have on its consolidated financial statements. Accounting Pronouncements adopted by the Company In May 2017, the FASB issued ASU No. 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting , which provides guidance about the changes to the terms and conditions of a share-based payment award that require an entity to apply modification accounting in "Stock Compensation (Topic 718)." The provisions of ASU No. 2017-09 are effective for reporting periods beginning after December 15, 2017; early adoption is permitted. The provisions of ASU No. 2017-09 are to be applied prospectively to an award modified on or after the adoption date. The Company early adopted the provisions of ASU No. 2017-09 during the third quarter of 2017 and the adoption of this standard update did not have a material impact on its consolidated financial statements. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments , which clarifies how cash receipts and cash payments in certain transactions are presented and classified on the statement of cash flows. The provisions of ASU No. 2016-15 are effective for reporting periods beginning after December 15, 2017, including interim periods, and will require adoption on a retrospective basis unless it is impracticable to apply, in which case we would be required to apply the amendments prospectively as of the earliest date practicable; early adoption is permitted. Upon adoption, cash payments made soon after the acquisition date of a business to settle a contingent consideration liability are classified as cash outflows for investing activities. Cash payments which are not made soon after the acquisition date of a business to settle a contingent consideration liability are separated and classified as cash outflows for financing activities up to the amount of the contingent consideration liability recognized at the acquisition date and as cash outflows from operating activities for any excess. The Company early adopted the provisions of ASU No. 2016-15 on January 1, 2017. As a result, $11.1 million of an acquisition-related contingent consideration payment of $15.0 million , which was in excess of the liability initially recognized at the acquisition date, has been classified as a cash outflow within net cash provided by operating activities in the accompanying consolidated statement of cash flows for the nine months ended September 30, 2017. In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . The Company adopted the provisions of ASU No. 2016-09 on January 1, 2017. Excess tax benefits or deficiencies related to equity awards to employees upon the exercise of stock options and the vesting of restricted stock units after January 1, 2017 are (i) reflected in the consolidated statement of operations as a component of the provision for income taxes, rather than recognized in equity, and (ii) reflected as operating, rather than financing, cash flows in our consolidated statement of cash flows. Excess tax benefits for the nine months ended September 30, 2017 were $314.3 million . Excess tax benefits of $43.1 million for the nine months ended September 30, 2016 were reclassified in the consolidated statement of cash flows to conform to the current year presentation. Upon adoption, the calculation of fully diluted shares excludes excess tax benefits from the assumed proceeds in applying the treasury stock method; previously such benefits were included in the calculation. This change increased fully diluted shares by approximately 1.1 million and 2.0 million shares for the three and nine months ended September 30, 2017 , respectively. The Company continues to account for forfeitures using an estimated forfeiture rate. In January 2017, the FASB issued ASU No. 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment , which is intended to simplify the accounting for goodwill impairment. The guidance eliminates the requirement to calculate the implied fair value of goodwill under today’s two-step impairment test to measure a goodwill impairment charge. The provisions of ASU No. 2017-04 are effective for reporting periods beginning after December 15, 2019; early adoption is permitted. The provisions of ASU No. 2017-04 are to be applied using a prospective approach. The Company early adopted the provisions of ASU No. 2017-04 on January 1, 2017 and the adoption of this standard update did not have a material impact on its consolidated financial statements.
Reclassifications	Reclassifications Certain prior year amounts have been reclassified to conform to the current year presentation.

BUSINESS COMBINATION (Tables)

BUSINESS COMBINATION (Tables)	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Schedule of Purchase Price	The table below summarizes the purchase price: Angie's List (In thousands) Class A common stock $ 763,684 Cash consideration for holders who elected to receive $8.50 in cash per share of Angie's List common stock 1,913 Fair value of vested and pro rata portion of unvested stock options attributable to pre-combination services 11,749 Fair value of the pro rata portion of unvested restricted stock units attributable to pre-combination services 4,038 Total purchase price $ 781,384
Schedule of Preliminary Estimated Fair Value of Assets Acquired and Liabilities Assumed	The table below summarizes the preliminary estimated fair values of the assets acquired and liabilities assumed at the date of combination: Angie's List (In thousands) Cash and cash equivalents $ 44,270 Other current assets 10,641 Property and equipment 16,341 Goodwill 545,396 Intangible assets 317,300 Total assets 933,948 Deferred revenue (32,130 ) Other current liabilities (46,106 ) Long-term debt—related party (61,498 ) Deferred income taxes (11,478 ) Other long-term liabilities (1,352 ) Net assets acquired $ 781,384
Schedule of Preliminary Estimated Fair Value of Intangible Assets Acquired	The preliminary estimated fair values of the identifiable intangible assets acquired at the date of combination are as follows: Angie's List (In thousands) Weighted-average useful life (years) Indefinite-lived trade names and trademarks $ 137,000 Indefinite Service providers 90,500 3 Developed technology 63,900 6 Memberships 15,900 3 User base 10,000 1 Total identifiable intangible assets acquired $ 317,300
Schedule of Pro Forma Financial Information	The unaudited pro forma financial information in the table below presents the combined results of the Company and Angie's List as if the Combination had occurred on January 1, 2016. The unaudited pro forma financial information includes adjustments required under the acquisition method of accounting and is presented for informational purposes only and is not necessarily indicative of the results that would have been achieved had the Combination actually occurred on January 1, 2016. For the three and nine months ended September 30, 2017 , pro forma adjustments include (i) reductions in stock-based compensation expense of $85.1 million and $52.8 million , respectively, and transaction related costs of $22.1 million and $25.6 million , respectively, because they are one-time in nature and will not have a continuing impact on operations; and (ii) an increase in amortization of intangibles of $11.4 million and $34.4 million , respectively. The stock-based compensation expense is related to the modification of previously issued HomeAdvisor vested equity awards, which were converted into ANGI Homeservices' equity awards, and the acceleration of previously issued Angie's List equity awards held by employees terminated in connection with the Combination. The transaction related costs include severance and retention costs of $12.0 million related to the Combination. For the three and nine months ended September 30, 2016 , pro forma adjustments include a reduction in revenue of $5.0 million and $31.4 million , respectively, due to the write-off of deferred revenue at the date of acquisition as well as increases in stock-based compensation expense of $19.7 million and $51.4 million , respectively, and amortization of intangibles of $14.0 million and $42.1 million , respectively. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands, except per share data) Revenue $ 898,584 $ 838,834 $ 2,571,613 $ 2,544,019 Net earnings (loss) attributable to IAC shareholders 244,400 12,237 313,054 (221,446 ) Basic earnings (loss) per share attributable to IAC shareholders 3.02 0.15 3.94 (2.76 ) Diluted earnings (loss) per share attributable to IAC shareholders 2.80 0.15 3.70 (2.76 )

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS (Tables)	9 Months Ended
	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill and Intangible Assets	Goodwill and intangible assets, net are as follows: September 30, December 31, 2017 2016 (In thousands) Goodwill $ 2,501,589 $ 1,924,052 Intangible assets with indefinite lives 460,333 320,645 Intangible assets with definite lives, net 199,770 34,806 Total goodwill and intangible assets, net $ 3,161,692 $ 2,279,503
Schedule of Goodwill by Reportable Segment	The following table presents the balance of goodwill by reportable segment, including the changes in the carrying value of goodwill, for the year ended December 31, 2016 : Balance at Additions (Deductions) Impairment Foreign Balance at (In thousands) Match Group $ 1,218,607 $ 603 $ (2,983 ) $ — $ (9,689 ) $ 1,206,538 ANGI Homeservices 150,251 21,985 — — (1,625 ) 170,611 Video 15,590 9,649 — — — 25,239 Applications 447,242 — — — — 447,242 Publishing 277,192 — (1,968 ) (275,367 ) 143 — Other 136,482 — (62,860 ) — 800 74,422 Total $ 2,245,364 $ 32,237 $ (67,811 ) $ (275,367 ) $ (10,371 ) $ 1,924,052 The following table presents the balance of goodwill by reportable segment, including the changes in the carrying value of goodwill, for the nine months ended September 30, 2017 : Balance at Additions (Deductions) Foreign Balance at (In thousands) Match Group $ 1,206,538 $ 255 $ — $ 43,575 $ 1,250,368 ANGI Homeservices 170,611 593,880 — 7,865 772,356 Video 25,239 6,384 — — 31,623 Applications 447,242 — — — 447,242 Other 74,422 — (74,430 ) 8 — Total $ 1,924,052 $ 600,519 $ (74,430 ) $ 51,448 $ 2,501,589
Schedule of Definite-Lived Intangible Assets	At September 30, 2017 and December 31, 2016 , intangible assets with definite lives are as follows: September 30, 2017 Gross Accumulated Net Weighted-Average (In thousands) Advertiser and supplier relationships and other $ 119,029 $ (4,654 ) $ 114,375 3.0 Technology 104,876 (32,348 ) 72,528 4.9 Customer lists and user base 13,911 (2,973 ) 10,938 1.1 Content 5,000 (3,723 ) 1,277 5.0 Trade names 14,518 (13,866 ) 652 2.7 Total $ 257,334 $ (57,564 ) $ 199,770 3.7 December 31, 2016 Gross Accumulated Net Weighted-Average (In thousands) Advertiser and supplier relationships and other $ 7,230 $ (2,612 ) $ 4,618 4.5 Technology 38,602 (27,667 ) 10,935 3.4 Customer lists 12,485 (9,997 ) 2,488 3.7 Content 14,802 (8,965 ) 5,837 4.3 Trade names 63,855 (52,927 ) 10,928 1.8 Total $ 136,974 $ (102,168 ) $ 34,806 2.8
Schedule of Definite-Lived Intangible Assets, Future Amortization Expense	At September 30, 2017 , amortization of intangible assets with definite lives for each of the next five years is estimated to be as follows: Years Ending September 30, (In thousands) 2018 $ 68,567 2019 51,422 2020 47,775 2021 10,735 2022 10,650 Thereafter 10,621 Total $ 199,770

FAIR VALUE MEASUREMENTS AND F27

FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present the Company's financial instruments that are measured at fair value on a recurring basis: September 30, 2017 Quoted Market Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Measurements (In thousands) Assets: Cash equivalents: Money market funds $ 865,630 $ — $ — $ 865,630 Time deposits — 105,942 — 105,942 Treasury discount notes 1,199 — — 1,199 Certificates of deposit — 6,199 — 6,199 Total $ 866,829 $ 112,141 $ — $ 978,970 Liabilities: Contingent consideration arrangement $ — $ — $ (1,792 ) $ (1,792 ) December 31, 2016 Quoted Market Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Measurements (In thousands) Assets: Cash equivalents: Money market funds $ 667,662 $ — $ — $ 667,662 Commercial paper — 123,640 — 123,640 Time deposits — 79,000 — 79,000 Treasury discount notes 24,991 — — 24,991 Marketable securities: Commercial paper — 49,797 — 49,797 Treasury discount notes 34,974 — — 34,974 Corporate debt securities — 4,571 — 4,571 Total $ 727,627 $ 257,008 $ — $ 984,635 Liabilities: Contingent consideration arrangements $ — $ — $ (33,871 ) $ (33,871 )
Schedule of Changes in Assets Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)	The following tables present the changes in the Company's financial instruments that are measured at fair value on a recurring basis using significant unobservable inputs (Level 3): Contingent Consideration Arrangements Three Months Ended September 30, 2017 2016 (In thousands) Balance at July 1 $ (24,829 ) $ (45,526 ) Total net (losses) gains: Included in earnings: Fair value adjustments (60 ) 2,477 Included in other comprehensive loss (332 ) (333 ) Settlements 23,429 30 Balance at September 30 $ (1,792 ) $ (43,352 ) Nine Months Ended September 30, 2017 2016 Contingent Consideration Arrangements Auction Rate Security Contingent Consideration Arrangements (In thousands) Balance at January 1 $ (33,871 ) $ 4,050 $ (33,873 ) Total net (losses) gains: Included in earnings: Fair value adjustments (4,945 ) — (7,993 ) Included in other comprehensive (loss) income (1,405 ) 5,950 (5,614 ) Fair value at date of acquisition — — 1,948 Settlements 38,429 — 2,180 Proceeds from sale — (10,000 ) — Balance at September 30 $ (1,792 ) $ — $ (43,352 )
Schedule of Changes in Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Level 3)	The following tables present the changes in the Company's financial instruments that are measured at fair value on a recurring basis using significant unobservable inputs (Level 3): Contingent Consideration Arrangements Three Months Ended September 30, 2017 2016 (In thousands) Balance at July 1 $ (24,829 ) $ (45,526 ) Total net (losses) gains: Included in earnings: Fair value adjustments (60 ) 2,477 Included in other comprehensive loss (332 ) (333 ) Settlements 23,429 30 Balance at September 30 $ (1,792 ) $ (43,352 ) Nine Months Ended September 30, 2017 2016 Contingent Consideration Arrangements Auction Rate Security Contingent Consideration Arrangements (In thousands) Balance at January 1 $ (33,871 ) $ 4,050 $ (33,873 ) Total net (losses) gains: Included in earnings: Fair value adjustments (4,945 ) — (7,993 ) Included in other comprehensive (loss) income (1,405 ) 5,950 (5,614 ) Fair value at date of acquisition — — 1,948 Settlements 38,429 — 2,180 Proceeds from sale — (10,000 ) — Balance at September 30 $ (1,792 ) $ — $ (43,352 )
Carrying Value and the Fair Value of Financial Instruments Measured at Fair Value Only for Disclosure Purposes	The following table presents the carrying value and the fair value of financial instruments measured at fair value only for disclosure purposes: September 30, 2017 December 31, 2016 Carrying Fair Carrying Fair (In thousands) Current portion of long-term debt $ — $ — $ (20,000 ) $ (20,311 ) Long-term debt, net of current portion (1,649,267 ) (1,720,311 ) (1,582,484 ) (1,657,861 )

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Schedule of Long-term Debt	Long-term debt consists of: September 30, 2017 December 31, 2016 (In thousands) Match Group Debt: 6.75% Senior Notes due December 15, 2022 (the "Match Group 6.75% Senior Notes"); interest payable each June 15 and December 15, which commenced June 15, 2016 $ 445,172 $ 445,172 6.375% Senior Notes due June 1, 2024 (the "Match Group 6.375% Senior Notes"); interest payable each June 1 and December 1, which commenced December 1, 2016 400,000 400,000 Match Group Term Loan due November 16, 2022 (a) 425,000 350,000 Total Match Group long-term debt 1,270,172 1,195,172 Less: Unamortized original issue discount and original issue premium, net 4,470 5,245 Less: Unamortized debt issuance costs 11,704 13,434 Total Match Group debt 1,253,998 1,176,493 IAC Debt: 4.875% Senior Notes due November 30, 2018 (the "4.875% Senior Notes"); interest payable each May 30 and November 30, which commenced May 30, 2014 361,874 390,214 4.75% Senior Notes due December 15, 2022 (the "4.75% Senior Notes"); interest payable each June 15 and December 15, which commenced June 15, 2013 34,859 38,109 Total IAC long-term debt 396,733 428,323 Less: Current portion of IAC long-term debt — 20,000 Less: Unamortized debt issuance costs 1,464 2,332 Total IAC debt, net of current portion 395,269 405,991 Total long-term debt, net of current portion $ 1,649,267 $ 1,582,484 ________________________ (a) The Match Group Term Loan matures on November 16, 2022; provided that, if any of the Match Group 6.75% Senior Notes remain outstanding on the date that is 91 days prior to the maturity date of the Match Group 6.75% Senior Notes, the Match Group Term Loan maturity date shall be September 15, 2022, the date that is 91 days prior to the maturity date of the Match Group 6.75% Senior Notes.

ACCUMULATED OTHER COMPREHENSI29

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Schedule of Accumulated Other Comprehensive (Loss) Income	The following tables present the components of accumulated other comprehensive (loss) income and items reclassified out of accumulated other comprehensive loss into earnings: Three Months Ended September 30, 2017 Foreign Currency Translation Adjustment Unrealized Gains On Available-For-Sale Securities Accumulated Other Comprehensive (Loss) Income (In thousands) Balance at July 1 $ (136,738 ) $ — $ (136,738 ) Other comprehensive income before reclassifications 37,225 — 37,225 Amounts reclassified to earnings — — — Net current period other comprehensive income 37,225 — 37,225 Balance at September 30 $ (99,513 ) $ — $ (99,513 ) Three Months Ended September 30, 2016 Foreign Currency Translation Adjustment Unrealized Gains (Losses) On Available-For-Sale Securities Accumulated Other Comprehensive Loss (In thousands) Balance at July 1 $ (121,612 ) $ 4,205 $ (117,407 ) Other comprehensive (loss) income before reclassifications, net of tax provision of $0.1 million related to unrealized losses on available-for-sale securities (5,132 ) 114 (5,018 ) Amounts reclassified to earnings — (259 ) (a) (259 ) Net current period other comprehensive loss (5,132 ) (145 ) (5,277 ) Balance at September 30 $ (126,744 ) $ 4,060 $ (122,684 ) ___________________ (a) Amount is net of a tax provision of $0.2 million . Nine Months Ended September 30, 2017 Foreign Currency Translation Adjustment Unrealized Gains On Available-For-Sale Securities Accumulated Other Comprehensive (Loss) Income (In thousands) Balance at January 1 $ (170,149 ) $ 4,026 $ (166,123 ) Other comprehensive income before reclassifications 69,951 7 69,958 Amounts reclassified to earnings 685 (4,033 ) (b) (3,348 ) Net current period other comprehensive income (loss) 70,636 (4,026 ) 66,610 Balance as of September 30 $ (99,513 ) $ — $ (99,513 ) ___________________ (b) Amount includes a tax benefit of $3.8 million . Nine Months Ended September 30, 2016 Foreign Currency Translation Adjustment Unrealized Gains On Available-For-Sale Securities Accumulated Other Comprehensive (Loss) Income (In thousands) Balance as of January 1 $ (154,645 ) $ 2,542 $ (152,103 ) Other comprehensive (loss) income before reclassifications, net of tax benefit of $0.7 million related to unrealized losses on available-for-sale securities (3,538 ) 4,868 1,330 Amounts reclassified to earnings 9,850 (2,892 ) (c) 6,958 Net current period other comprehensive income 6,312 1,976 8,288 Reallocation of accumulated other comprehensive loss (income) related to the noncontrolling interests created in the Match Group initial public offering 21,589 (458 ) 21,131 Balance as of September 30 $ (126,744 ) $ 4,060 $ (122,684 ) ___________________ (c) Amount is net of a tax provision of $0.2 million . At September 30, 2017, there was no tax benefit or provision on the accumulated other comprehensive loss.

EARNINGS (LOSS) PER SHARE (Tabl

EARNINGS (LOSS) PER SHARE (Tables)	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings (Loss) Per Share	The following table sets forth the computation of basic and diluted earnings (loss) per share attributable to IAC shareholders: Three Months Ended September 30, 2017 2016 Basic Diluted Basic Diluted (In thousands, except per share data) Numerator: Net earnings $ 225,639 $ 225,639 $ 52,340 $ 52,340 Net earnings attributable to noncontrolling interests (45,996 ) (45,996 ) (9,178 ) (9,178 ) Impact from public subsidiaries' dilutive securities (a) — (23,749 ) — (3,473 ) Net earnings attributable to IAC shareholders $ 179,643 $ 155,894 $ 43,162 $ 39,689 Denominator: Weighted average basic shares outstanding 80,817 80,817 79,532 79,532 Dilutive securities including stock options and RSUs and subsidiary denominated equity awards (b)(c)(e) — 6,379 — 2,087 Denominator for earnings per share—weighted average shares (b)(c)(e) 80,817 87,196 79,532 81,619 Earnings per share attributable to IAC shareholders: Earnings per share $ 2.22 $ 1.79 $ 0.54 $ 0.49 Nine Months Ended September 30, 2017 2016 Basic Diluted Basic Diluted (In thousands, except per share data) Numerator: Net earnings (loss) $ 334,659 $ 334,659 $ (130,268 ) $ (130,268 ) Net earnings attributable to noncontrolling interests (62,539 ) (62,539 ) (13,063 ) (13,063 ) Impact from public subsidiaries dilutive securities (a) — (34,104 ) — — Net earnings (loss) attributable to IAC shareholders $ 272,120 $ 238,016 $ (143,331 ) $ (143,331 ) Denominator: Weighted average basic shares outstanding 79,369 79,369 80,357 80,357 Dilutive securities including stock options and RSUs and subsidiary denominated equity awards (b)(c)(d)(e) — 5,133 — — Denominator for earnings per share—weighted average shares (b)(c)(d)(e) 79,369 84,502 80,357 80,357 Earnings (loss) per share attributable to IAC shareholders: Earnings (loss) per share $ 3.43 $ 2.82 $ (1.78 ) $ (1.78 ) ________________________ (a) The amount for the three and nine months ended September 30, 2017 and for the three months ended September 30, 2016 reflects the reduction in Match Group's earnings attributable to IAC from the assumed exercise of Match Group dilutive securities under the if-converted method. For the nine months ended September 30, 2016 , the impact on earnings related to Match Group's dilutive securities under the if-converted method is excluded because it would have been anti-dilutive due to the Company's net loss. (b) Dilutive securities for the three and nine months ended September 30, 2017 , includes the impact from the assumed exercise of ANGI Homeservices dilutive securities under the if-converted method, as it is more dilutive for IAC to settle certain ANGI Homeservices equity awards. The impact on earnings of ANGI Homeservices dilutive securities is not applicable for priors prior to the Combination. (c) If the effect is dilutive, weighted average common shares outstanding include the incremental shares that would be issued upon the assumed exercise of stock options and subsidiary denominated equity and vesting of restricted stock units ("RSUs"). For the three months ended September 30, 2017 , there were no potentially dilutive securities excluded from the calculation of diluted earnings per share. For the nine months ended September 30, 2017 and three months ended September 30, 2016 , less than 0.1 million and 3.3 million potentially dilutive securities, respectively, are excluded from the calculation of diluted earnings per share because their inclusion would have been anti-dilutive. (d) For the nine months ended September 30, 2016 , the Company had a loss from operations and, as a result, approximately 9.8 million potentially dilutive securities were excluded from computing diluted earnings per share because the impact would have been anti-dilutive. Accordingly, the weighted average basic shares outstanding were used to compute the diluted earnings per share amount. (e) Market-based awards and performance-based stock units (“PSUs”) are considered contingently issuable shares. Shares issuable upon exercise or vesting of market-based awards and PSUs are included in the denominator for earnings per share if (i) the applicable market or performance condition(s) has been met and (ii) the inclusion of the market-based awards and PSUs is dilutive for the respective reporting periods. For the three and nine months ended September 30, 2017 and three months ended September 30, 2016 , 0.3 million shares underlying market-based awards and PSUs were excluded from the calculation of diluted earnings per share because the market or performance conditions had not been met.

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Schedule of Segment Reporting Information	Operating segments are combined for reporting purposes if they meet certain aggregation criteria, which principally relate to the similarity of their economic characteristics or, in the case of the Other reportable segment, do not meet the quantitative thresholds that require presentation as separate reportable segments. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Revenue: Match Group $ 343,418 $ 287,530 $ 951,754 $ 823,240 ANGI Homeservices 181,717 133,560 513,173 375,222 Video 78,338 59,955 184,097 162,361 Applications 136,333 142,782 439,199 445,735 Publishing 88,755 74,902 244,959 326,195 Other (a) — 65,515 23,980 196,323 Inter-segment eliminations (127 ) (142 ) (508 ) (356 ) Total $ 828,434 $ 764,102 $ 2,356,654 $ 2,328,720 ___________________ (a) The Other segment consists of the results of PriceRunner, ShoeBuy and The Princeton Review for periods prior to the sale of these businesses, which occurred on March 18, 2016, December 30, 2016 and March 31, 2017, respectively. Beginning in the second quarter of 2017, as a result of the sale of these businesses, the Other segment does not include any financial results. Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Operating Income (Loss): Match Group $ 91,008 $ 90,938 $ 232,854 $ 202,624 ANGI Homeservices (112,505 ) 10,148 (115,258 ) 19,147 Video (1,809 ) (2,663 ) (25,227 ) (25,187 ) Applications 29,386 29,240 101,288 75,839 Publishing 5,677 (14,562 ) (2,968 ) (324,720 ) Other — (695 ) (5,621 ) (11,313 ) Corporate (30,346 ) (26,822 ) (90,962 ) (81,835 ) Total $ (18,589 ) $ 85,584 $ 94,106 $ (145,445 ) Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Adjusted EBITDA: (b) Match Group $ 119,564 $ 107,101 $ 315,705 $ 275,834 ANGI Homeservices (2,266 ) 15,291 21,612 33,927 Video (822 ) (894 ) (22,386 ) (21,770 ) Applications 31,077 34,575 106,556 94,715 Publishing 7,088 (6,208 ) 11,007 (6,639 ) Other — 2,783 (1,532 ) (1,129 ) Corporate (17,070 ) (13,662 ) (46,908 ) (38,030 ) Total $ 137,571 $ 138,986 $ 384,054 $ 336,908 ________________________ (b) The Company's primary financial measure is Adjusted EBITDA, which is defined as operating income excluding: (1) stock-based compensation expense; (2) depreciation; and (3) acquisition-related items consisting of (i) amortization of intangible assets and impairments of goodwill and intangible assets, if applicable, and (ii) gains and losses recognized on changes in the fair value of contingent consideration arrangements. The Company believes this measure is useful for analysts and investors as this measure allows a more meaningful comparison between our performance and that of our competitors. Moreover, our management uses this measure internally to evaluate the performance of our business as a whole and our individual business segments, and this measure is one of the primary metrics by which our internal budgets are based and by which management is compensated. The above items are excluded from our Adjusted EBITDA measure because these items are non-cash in nature, and we believe that by excluding these items, Adjusted EBITDA corresponds more closely to the cash operating income generated from our business, from which capital investments are made and debt is serviced. Adjusted EBITDA has certain limitations in that it does not take into account the impact to IAC's statement of operations of certain expenses. The following table presents the revenue of the Company's principal segments disaggregated by type of service: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Match Group Direct revenue $ 330,098 $ 273,727 $ 917,273 $ 786,176 Indirect revenue (principally advertising revenue) 13,320 13,803 34,481 37,064 Total Match Group revenue $ 343,418 $ 287,530 $ 951,754 $ 823,240 ANGI Homeservices Consumer connection revenue (c) $ 151,056 $ 110,874 $ 427,854 $ 310,962 Membership subscription revenue 22,146 14,083 61,145 40,008 Other 8,515 8,603 24,174 24,252 Total ANGI Homeservices revenue $ 181,717 $ 133,560 $ 513,173 $ 375,222 Applications Advertising $ 121,425 $ 129,027 $ 390,160 $ 409,212 Subscription (including downloadable app fees) and other 14,908 13,755 49,039 36,523 Total Applications revenue $ 136,333 $ 142,782 $ 439,199 $ 445,735 Publishing Advertising $ 87,788 $ 74,272 $ 242,957 $ 324,422 Other 967 630 2,002 1,773 Total Publishing revenue $ 88,755 $ 74,902 $ 244,959 $ 326,195 ___________________ (c) Fees paid by service professionals for consumer matches.
Schedule of Revenue and Long-lived Assets, Excluding Goodwill and Intangible Assets, by Geography	Revenue by geography is based on where the customer is located. Geographic information about revenue and long-lived assets is presented below: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Revenue: United States $ 577,362 $ 567,132 $ 1,670,980 $ 1,721,348 All other countries 251,072 196,970 685,674 607,372 Total $ 828,434 $ 764,102 $ 2,356,654 $ 2,328,720 September 30, December 31, (In thousands) Long-lived assets (excluding goodwill and intangible assets): United States $ 293,005 $ 281,725 All other countries 27,272 24,523 Total $ 320,277 $ 306,248
Schedule of Reconciliation of Operating Income (Loss) to Adjusted EBITDA	The following tables reconcile operating income (loss) for the Company's reportable segments and net earnings (loss) attributable to IAC shareholders to Adjusted EBITDA: Three Months Ended September 30, 2017 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Adjusted EBITDA (In thousands) Match Group $ 91,008 $ 19,949 $ 8,147 $ 401 $ 59 $ 119,564 ANGI Homeservices (112,505 ) 103,980 3,491 2,768 — (2,266 ) Video (1,809 ) 134 541 312 — (822 ) Applications 29,386 — 1,155 536 — 31,077 Publishing 5,677 — 1,062 349 — 7,088 Other — — — — — — Corporate (30,346 ) 10,409 2,867 — — (17,070 ) Total (18,589 ) $ 134,472 $ 17,263 $ 4,366 $ 59 $ 137,571 Interest expense (25,036 ) Other expense, net (10,216 ) Loss before income taxes (53,841 ) Income tax benefit 279,480 Net earnings 225,639 Net earnings attributable to noncontrolling interests (45,996 ) Net earnings attributable to IAC shareholders $ 179,643 Three Months Ended September 30, 2016 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Adjusted EBITDA (In thousands) Match Group $ 90,938 $ 10,718 $ 7,192 $ 3,382 $ (5,129 ) $ 107,101 ANGI Homeservices 10,148 2,391 2,026 726 — 15,291 Video (2,663 ) 640 438 691 — (894 ) Applications 29,240 — 1,073 1,519 2,743 34,575 Publishing (14,562 ) — 2,029 6,325 — (6,208 ) Other (695 ) 427 1,518 1,624 (91 ) 2,783 Corporate (26,822 ) 9,485 3,675 — — (13,662 ) Total 85,584 $ 23,661 $ 17,951 $ 14,267 $ (2,477 ) $ 138,986 Interest expense (27,118 ) Other income, net 11,700 Earnings before income taxes 70,166 Income tax provision (17,826 ) Net earnings 52,340 Net earnings attributable to noncontrolling interests (9,178 ) Net earnings attributable to IAC shareholders $ 43,162 Nine Months Ended September 30, 2017 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Adjusted EBITDA (In thousands) Match Group $ 232,854 $ 53,627 $ 23,619 $ 1,208 $ 4,397 $ 315,705 ANGI Homeservices (115,258 ) 120,280 9,705 6,885 — 21,612 Video (25,227 ) 267 1,637 937 — (22,386 ) Applications 101,288 — 3,087 1,633 548 106,556 Publishing (2,968 ) — 4,011 9,964 — 11,007 Other (5,621 ) 1,729 836 1,524 — (1,532 ) Corporate (90,962 ) 31,459 12,595 — — (46,908 ) Total 94,106 $ 207,362 $ 55,490 $ 22,151 $ 4,945 $ 384,054 Interest expense (74,556 ) Other expense, net (7,700 ) Earnings before income taxes 11,850 Income tax benefit 322,809 Net earnings 334,659 Net earnings attributable to noncontrolling interests (62,539 ) Net earnings attributable to IAC shareholders $ 272,120 Nine Months Ended September 30, 2016 Operating Income (Loss) Stock-Based Compensation Expense Depreciation Amortization of Intangibles Acquisition-related Contingent Consideration Fair Value Adjustments Goodwill Impairment Adjusted EBITDA (In thousands) Match Group $ 202,624 $ 40,810 $ 20,119 $ 15,004 $ (2,723 ) $ — $ 275,834 ANGI Homeservices 19,147 6,685 5,824 2,271 — — 33,927 Video (25,187 ) 640 1,313 1,656 (192 ) — (21,770 ) Applications 75,839 — 3,304 4,573 10,999 — 94,715 Publishing (324,720 ) — 6,366 36,348 — 275,367 (6,639 ) Other (11,313 ) 531 4,534 5,210 (91 ) — (1,129 ) Corporate (81,835 ) 33,944 9,861 — — — (38,030 ) Total (145,445 ) $ 82,610 $ 51,321 $ 65,062 $ 7,993 $ 275,367 $ 336,908 Interest expense (82,622 ) Other income, net 20,405 Loss before income taxes (207,662 ) Income tax benefit 77,394 Net loss (130,268 ) Net earnings attributable to noncontrolling interests (13,063 ) Net loss attributable to IAC shareholders $ (143,331 )

CONSOLIDATED FINANCIAL STATEM32

CONSOLIDATED FINANCIAL STATEMENT DETAILS (Tables)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Other (Expense) Income, Net	Other (expense) income, net consists of: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (In thousands) Other (expense) income, net $ (10,216 ) $ 11,700 $ (7,700 ) $ 20,405

GUARANTOR AND NON-GUARANTOR F33

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION (Tables)	9 Months Ended
	Sep. 30, 2017
Guarantor and Nonguarantor Financial Statements [Abstract]
Schedule of Condensed Balance Sheet	Balance sheet at September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Cash and cash equivalents $ 501,918 $ — $ 753,399 $ — $ 1,255,317 Accounts receivable, net — 81,448 189,761 — 271,209 Other current assets 59,319 21,305 119,753 — 200,377 Intercompany receivables — 754,376 1,280,777 (2,035,153 ) — Property and equipment, net 3,163 160,968 156,146 — 320,277 Goodwill — 412,010 2,089,579 — 2,501,589 Intangible assets, net — 75,627 584,476 — 660,103 Investment in subsidiaries 4,489,006 549,342 — (5,038,348 ) — Other non-current assets 50,991 115,668 356,853 (191,429 ) 332,083 Total assets $ 5,104,397 $ 2,170,744 $ 5,530,744 $ (7,264,930 ) $ 5,540,955 Accounts payable $ 2,521 $ 23,806 $ 78,479 $ — $ 104,806 Other current liabilities 50,523 69,445 610,752 — 730,720 Long-term debt, net of current portion 395,269 — 1,253,998 — 1,649,267 Income taxes payable 11 3,270 30,009 — 33,290 Intercompany liabilities 2,035,153 — — (2,035,153 ) — Other long-term liabilities 191,999 18,741 53,877 (191,429 ) 73,188 Redeemable noncontrolling interests — — 40,981 — 40,981 IAC shareholders' equity 2,428,921 2,055,482 2,982,866 (5,038,348 ) 2,428,921 Noncontrolling interests — — 479,782 — 479,782 Total liabilities and shareholders' equity $ 5,104,397 $ 2,170,744 $ 5,530,744 $ (7,264,930 ) $ 5,540,955 Balance sheet at December 31, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Cash and cash equivalents $ 553,643 $ — $ 775,544 $ — $ 1,329,187 Marketable securities 89,342 — — — 89,342 Accounts receivable, net — 77,335 142,803 — 220,138 Other current assets 71,152 36,154 96,762 — 204,068 Intercompany receivables — 650,595 1,123,925 (1,774,520 ) — Property and equipment, net 4,350 159,304 142,594 — 306,248 Goodwill — 412,010 1,512,042 — 1,924,052 Intangible assets, net — 83,179 272,272 — 355,451 Investment in subsidiaries 3,659,570 523,814 — (4,183,384 ) — Other non-current assets 52,228 115,150 165,482 (115,473 ) 217,387 Total assets $ 4,430,285 $ 2,057,541 $ 4,231,424 $ (6,073,377 ) $ 4,645,873 Current portion of long-term debt $ 20,000 $ — $ — $ — $ 20,000 Accounts payable 2,697 29,867 30,299 — 62,863 Other current liabilities 42,441 84,629 503,455 — 630,525 Long-term debt, net of current portion 405,991 — 1,176,493 — 1,582,484 Income taxes payable — 3,470 30,274 (216 ) 33,528 Intercompany liabilities 1,774,520 — — (1,774,520 ) — Other long-term liabilities 315,414 20,952 51,867 (115,257 ) 272,976 Redeemable noncontrolling interests — — 32,827 — 32,827 IAC shareholders' equity 1,869,222 1,918,623 2,264,761 (4,183,384 ) 1,869,222 Noncontrolling interests — — 141,448 — 141,448 Total liabilities and shareholders' equity $ 4,430,285 $ 2,057,541 $ 4,231,424 $ (6,073,377 ) $ 4,645,873
Schedule of Condensed Income Statement	Statement of operations for the three months ended September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 185,386 $ 643,175 $ (127 ) $ 828,434 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) — 41,741 124,676 (127 ) 166,290 Selling and marketing expense 312 84,416 268,181 (30 ) 352,879 General and administrative expense 32,060 15,676 187,814 30 235,580 Product development expense 593 13,145 56,907 — 70,645 Depreciation 406 3,822 13,035 — 17,263 Amortization of intangibles — 350 4,016 — 4,366 Total operating costs and expenses 33,371 159,150 654,629 (127 ) 847,023 Operating (loss) income (33,371 ) 26,236 (11,454 ) — (18,589 ) Equity in earnings of unconsolidated affiliates 203,808 4,229 — (208,037 ) — Interest expense (5,483 ) — (19,553 ) — (25,036 ) Other (expense) income, net (8,157 ) 8,311 (10,370 ) — (10,216 ) Earnings (loss) before income taxes 156,797 38,776 (41,377 ) (208,037 ) (53,841 ) Income tax benefit (provision) 22,846 (11,710 ) 268,344 — 279,480 Net earnings 179,643 27,066 226,967 (208,037 ) 225,639 Net earnings attributable to noncontrolling interests — — (45,996 ) — (45,996 ) Net earnings attributable to IAC shareholders $ 179,643 $ 27,066 $ 180,971 $ (208,037 ) $ 179,643 Comprehensive income attributable to IAC shareholders $ 216,868 $ 26,789 $ 224,929 $ (251,718 ) $ 216,868 Statement of operations for the three months ended September 30, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 206,107 $ 558,154 $ (159 ) $ 764,102 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) 219 63,730 115,226 (44 ) 179,131 Selling and marketing expense 546 87,051 205,620 (221 ) 292,996 General and administrative expense 22,375 20,243 81,745 106 124,469 Product development expense 1,009 16,453 32,242 — 49,704 Depreciation 422 6,051 11,478 — 17,951 Amortization of intangibles — 6,100 8,167 — 14,267 Total operating costs and expenses 24,571 199,628 454,478 (159 ) 678,518 Operating (loss) income (24,571 ) 6,479 103,676 — 85,584 Equity in earnings (losses) of unconsolidated affiliates 71,471 (22,707 ) — (48,764 ) — Interest expense (6,362 ) — (20,756 ) — (27,118 ) Other (expense) income, net (6,334 ) 4,837 13,197 — 11,700 Earnings (loss) before income taxes 34,204 (11,391 ) 96,117 (48,764 ) 70,166 Income tax benefit (provision) 8,958 (4,263 ) (22,521 ) — (17,826 ) Net earnings (loss) 43,162 (15,654 ) 73,596 (48,764 ) 52,340 Net earnings attributable to noncontrolling interests — — (9,178 ) — (9,178 ) Net earnings (loss) attributable to IAC shareholders $ 43,162 $ (15,654 ) $ 64,418 $ (48,764 ) $ 43,162 Comprehensive income (loss) attributable to IAC shareholders $ 37,885 $ (15,605 ) $ 59,542 $ (43,937 ) $ 37,885 Statement of operations for the nine months ended September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 536,789 $ 1,820,373 $ (508 ) $ 2,356,654 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) 159 104,581 346,975 (434 ) 451,281 Selling and marketing expense 1,250 258,634 763,640 (130 ) 1,023,394 General and administrative expense 93,974 46,777 388,590 56 529,397 Product development expense 2,098 42,324 136,413 — 180,835 Depreciation 1,290 15,799 38,401 — 55,490 Amortization of intangibles — 10,102 12,049 — 22,151 Total operating costs and expenses 98,771 478,217 1,686,068 (508 ) 2,262,548 Operating (loss) income (98,771 ) 58,572 134,305 — 94,106 Equity in earnings of unconsolidated affiliates 346,643 8,170 — (354,813 ) — Interest expense (16,960 ) — (57,596 ) — (74,556 ) Other (expense) income, net (20,783 ) 21,207 (8,124 ) — (7,700 ) Earnings before income taxes 210,129 87,949 68,585 (354,813 ) 11,850 Income tax benefit (provision) 61,991 (22,651 ) 283,469 — 322,809 Net earnings 272,120 65,298 352,054 (354,813 ) 334,659 Net earnings attributable to noncontrolling interests — — (62,539 ) — (62,539 ) Net earnings attributable to IAC shareholders $ 272,120 $ 65,298 $ 289,515 $ (354,813 ) $ 272,120 Comprehensive income attributable to IAC shareholders $ 338,730 $ 67,276 $ 373,635 $ (440,911 ) $ 338,730 Statement of operations for the nine months ended September 30, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Revenue $ — $ 710,915 $ 1,618,178 $ (373 ) $ 2,328,720 Operating costs and expenses: Cost of revenue (exclusive of depreciation shown separately below) 811 201,326 341,346 (221 ) 543,262 Selling and marketing expense 2,306 323,681 646,777 (274 ) 972,490 General and administrative expense 66,208 65,491 272,475 122 404,296 Product development expense 4,127 55,334 102,906 — 162,367 Depreciation 1,274 17,144 32,903 — 51,321 Amortization of intangibles — 35,183 29,879 — 65,062 Goodwill impairment — 253,245 22,122 — 275,367 Total operating costs and expenses 74,726 951,404 1,448,408 (373 ) 2,474,165 Operating (loss) income (74,726 ) (240,489 ) 169,770 — (145,445 ) Equity in losses of unconsolidated affiliates (44,988 ) (29,893 ) — 74,881 — Interest expense (20,776 ) — (61,846 ) — (82,622 ) Other (expense) income, net (35,306 ) 11,251 44,460 — 20,405 (Loss) earnings before income taxes (175,796 ) (259,131 ) 152,384 74,881 (207,662 ) Income tax benefit (provision) 32,465 81,742 (36,813 ) — 77,394 Net (loss) earnings (143,331 ) (177,389 ) 115,571 74,881 (130,268 ) Net earnings attributable to noncontrolling interests — — (13,063 ) — (13,063 ) Net (loss) earnings attributable to IAC shareholders $ (143,331 ) $ (177,389 ) $ 102,508 $ 74,881 $ (143,331 ) Comprehensive (loss) income attributable to IAC shareholders $ (135,043 ) $ (157,069 ) $ 108,007 $ 49,062 $ (135,043 )
Schedule of Condensed Cash Flow Statement	Statement of cash flows for the nine months ended September 30, 2017: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Net cash (used in) provided by operating activities $ (35,286 ) $ 76,616 $ 256,267 $ — $ 297,597 Cash flows from investing activities: Acquisitions, net of cash acquired — (2,200 ) (66,913 ) — (69,113 ) Capital expenditures (337 ) (17,263 ) (38,919 ) — (56,519 ) Proceeds from maturities and sales of marketable debt securities 114,350 — — — 114,350 Purchases of marketable debt securities (24,909 ) — — — (24,909 ) Purchases of investments — — (9,105 ) — (9,105 ) Net proceeds from the sale of businesses and investments 911 — 124,309 — 125,220 Intercompany (108,258 ) — — 108,258 — Other, net — 307 1,012 — 1,319 Net cash (used in) provided by investing activities (18,243 ) (19,156 ) 10,384 108,258 81,243 Cash flows from financing activities: Purchase of IAC treasury stock (56,424 ) — — — (56,424 ) Proceeds from Match Group Term Loan — — 75,000 — 75,000 Debt issuance costs — — (2,637 ) — (2,637 ) Repurchases of IAC Senior Notes (31,590 ) — — — (31,590 ) Proceeds from the exercise of IAC stock options 69,065 — — — 69,065 Withholding taxes paid on behalf of IAC net settled stock-based awards (57,180 ) — — — (57,180 ) Proceeds from the exercise of Match Group stock options — — 57,705 — 57,705 Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards — — (501,437 ) — (501,437 ) Purchase of noncontrolling interests — — (13,011 ) — (13,011 ) Acquisition-related contingent consideration payments — — (27,289 ) — (27,289 ) Funds returned from escrow for MyHammer tender offer — — 10,604 — 10,604 Decrease in restricted cash related to bond redemptions 20,141 — — 20,141 Intercompany 57,460 (57,460 ) 108,258 (108,258 ) — Other, net 251 — (5,253 ) — (5,002 ) Net cash provided by (used in) financing activities 1,723 (57,460 ) (298,060 ) (108,258 ) (462,055 ) Total cash used (51,806 ) — (31,409 ) — (83,215 ) Effect of exchange rate changes on cash and cash equivalents 81 — 9,264 — 9,345 Net decrease in cash and cash equivalents (51,725 ) — (22,145 ) — (73,870 ) Cash and cash equivalents at beginning of period 553,643 — 775,544 — 1,329,187 Cash and cash equivalents at end of period $ 501,918 $ — $ 753,399 $ — $ 1,255,317 Statement of cash flows for the nine months ended September 30, 2016: IAC Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations IAC Consolidated (In thousands) Net cash (used in) provided by operating activities $ (60,394 ) $ 66,421 $ 188,232 $ — $ 194,259 Cash flows from investing activities: Acquisitions, net of cash acquired — — (2,524 ) — (2,524 ) Capital expenditures (343 ) (4,747 ) (57,649 ) — (62,739 ) Investments in time deposits — — (87,500 ) — (87,500 ) Proceeds from maturities of time deposits — — 87,500 — 87,500 Proceeds from maturities and sales of marketable debt securities 79,210 — — — 79,210 Purchases of marketable debt securities (229,246 ) — — — (229,246 ) Purchases of investments — — (7,211 ) — (7,211 ) Net proceeds from the sale of businesses and investments 15,401 1,779 93,356 — 110,536 Intercompany (58,998 ) — — 58,998 — Other, net — 158 5,404 — 5,562 Net cash (used in) provided by investing activities (193,976 ) (2,810 ) 31,376 58,998 (106,412 ) Cash flows from financing activities: Purchase of IAC treasury stock (247,256 ) — — — (247,256 ) Proceeds from Match Group 6.375% Senior Notes offering — — 400,000 — 400,000 Principal payment on Match Group Term Loan — — (410,000 ) — (410,000 ) Debt issuance costs — — (5,048 ) — (5,048 ) Repurchases of IAC Senior Notes (126,271 ) — — — (126,271 ) Proceeds from the exercise of IAC stock options 19,536 — — — 19,536 Withholding taxes paid on behalf of IAC net settled stock-based awards (26,684 ) — — — (26,684 ) Proceeds from the exercise of Match Group stock options — — 30,246 — 30,246 Withholding taxes paid on behalf of Match Group net settled stock-based awards — — (29,779 ) — (29,779 ) Purchase of noncontrolling interests (1,400 ) — (1,129 ) — (2,529 ) Acquisition-related contingent consideration payments — (351 ) (1,829 ) — (2,180 ) Decrease in restricted cash related to bond redemptions 20,000 — — — 20,000 Intercompany 63,261 (63,260 ) 58,997 (58,998 ) — Other, net — — (766 ) — (766 ) Net cash (used in) provided by financing activities (298,814 ) (63,611 ) 40,692 (58,998 ) (380,731 ) Total cash (used) provided (553,184 ) — 260,300 — (292,884 ) Effect of exchange rate changes on cash and cash equivalents — — 1,221 — 1,221 Net (decrease) increase in cash and cash equivalents (553,184 ) — 261,521 — (291,663 ) Cash and cash equivalents at beginning of period 1,074,658 — 406,789 — 1,481,447 Cash and cash equivalents at end of period $ 521,474 $ — $ 668,310 $ — $ 1,189,784

THE COMPANY AND SUMMARY OF SI34

THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Revenue and Other [Line Items]
Revenue	$ 828,434	$ 764,102	$ 2,356,654	$ 2,328,720
Accounts receivable, net	271,209		271,209		$ 220,138
Match Group
Revenue and Other [Line Items]
Capitalized mobile app store fees	19,800		19,800
Operating segments | Publishing
Revenue and Other [Line Items]
Revenue	88,755	74,902	244,959	326,195
Operating segments | Applications
Revenue and Other [Line Items]
Revenue	136,333	142,782	439,199	445,735
Operating segments | Match Group
Revenue and Other [Line Items]
Revenue	343,418	287,530	951,754	823,240
Google Inc.
Revenue and Other [Line Items]
Accounts receivable, net	62,000		62,000		$ 65,800
Google Inc. | Publishing and Applications
Revenue and Other [Line Items]
Revenue	$ 176,800	$ 172,000	$ 539,200	$ 638,200
Google Inc. | Revenue | Customer concentration risk
Revenue and Other [Line Items]
Concentration risk (as a percent)	21.00%	23.00%	23.00%	27.00%
Google Inc. | Revenue | Customer concentration risk | Operating segments | Publishing
Revenue and Other [Line Items]
Concentration risk (as a percent)	72.00%	66.00%	71.00%	76.00%
Google Inc. | Revenue | Customer concentration risk | Operating segments | Applications
Revenue and Other [Line Items]
Concentration risk (as a percent)	82.00%	85.00%	83.00%	87.00%

THE COMPANY AND SUMMARY OF SI35

THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - ANGI Homeservices Acquisition (Details) - $ / shares	Sep. 29, 2017	Sep. 30, 2017
Series C Preferred Stock
Business Acquisition [Line Items]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, dividend amount per annum (in dollars per share)	$ 75
Series C Preferred Stock | USANi LLC
Business Acquisition [Line Items]
Preferred shares issued	67,633
ANGI Homeservices
Business Acquisition [Line Items]
Ownership, economic interest		87.10%
Ownership, voting interest		98.50%

THE COMPANY AND SUMMARY OF SI36

THE COMPANY AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recently Adopted Standards (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Acquisition-related contingent consideration payment in operating activities		$ 11,140	$ 0
Acquisition-related contingent consideration payment		15,000
Excess tax benefit generated by settlement or exercise of stock-based awards		314,300
ASU No. 2016-15 | New Accounting Pronouncement, Early Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Acquisition-related contingent consideration payment in operating activities		$ 11,100
ASU No. 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in diluted shares as a result of adoption of new accounting standard (in shares)	1.1	2
ASU No. 2016-09 | Reclassification adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefit generated by settlement or exercise of stock-based awards			$ 43,100

INCOME TAXES - Narrative (Detai

INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income tax provision (benefit)	$ (279,480)	$ 17,826	$ (322,809)	$ (77,394)
Excess tax benefit generated by settlement or exercise of stock-based awards			314,300
Effective tax provision (benefit) rate (as a percent)		25.00%		(37.00%)
Federal statutory rate (as a percent)		35.00%		35.00%
Accrued interest on unrecognized tax benefits	3,300		3,300		$ 2,600
Accrued penalties on unrecognized tax benefits	1,700		1,700		1,700
Total unrecognized tax benefits including interest and penalties	43,000		43,000		41,000
Unrecognized tax benefit, if subsequently recognized would reduce income tax expense	39,400		39,400		$ 37,700
Decrease in unrecognized tax benefit, reasonably possible within twelve months	22,500		22,500
Decrease in unrecognized tax benefit which would reduce the income tax provision	22,000		22,000
Gross deferred tax asset	$ 221,500		$ 221,500

BUSINESS COMBINATION - Narrativ

BUSINESS COMBINATION - Narrative (Details) - Angie's List - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Sep. 29, 2017	Sep. 30, 2017	Sep. 30, 2017
Business Acquisition [Line Items]
Percentage of interest acquired	100.00%
Purchase price	$ 781,384
Common stock of acquiree outstanding prior to acquisition (in shares)	61.3
Share price paid in acquisition (in dollars per share)	$ 12.46
Cash consideration	$ 1,900
Cash per share paid to acquiree shareholders' who elected payout (in dollars per share)	$ 8.50
Revenue of acquiree since acquisition date		$ 700	$ 700
Net loss of acquiree since acquisition date		$ 20,000	$ 20,000

BUSINESS COMBINATION - Purchase

BUSINESS COMBINATION - Purchase Price (Details) - Angie's List $ / shares in Units, $ in Thousands	Sep. 29, 2017USD ($)$ / shares
Business Acquisition [Line Items]
Cash consideration for holders who elected to receive $8.50 in cash per share of Angie's List common stock	$ 1,900
Total purchase price	$ 781,384
Cash per share paid to acquiree shareholders' who elected payout (in dollars per share) | $ / shares	$ 8.50
Common Class A
Business Acquisition [Line Items]
Consideration transferred, equity interests	$ 763,684
Cash consideration for holders who elected to receive $8.50 in cash per share of Angie's List common stock	1,913
Common Class A | Stock Option
Business Acquisition [Line Items]
Consideration transferred, equity interests	11,749
Common Class A | Restricted Stock Units
Business Acquisition [Line Items]
Consideration transferred, equity interests	$ 4,038

BUSINESS COMBINATION - Prelimin

BUSINESS COMBINATION - Preliminary Estimated Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 29, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill	$ 2,501,589		$ 1,924,052	$ 2,245,364
Angie's List
Business Acquisition [Line Items]
Cash and cash equivalents		$ 44,270
Other current assets		10,641
Property and equipment		16,341
Goodwill		545,396
Intangible assets		317,300
Total assets		933,948
Deferred revenue		(32,130)
Other current liabilities		(46,106)
Long-term debt—related party		(61,498)
Deferred income taxes		(11,478)
Other long-term liabilities		(1,352)
Net assets acquired		$ 781,384

BUSINESS COMBINATION - Prelim41

BUSINESS COMBINATION - Preliminary Estimated Fair Value of Intangible Assets Acquired (Details) - USD ($) $ in Thousands	Sep. 29, 2017	Sep. 30, 2017	Dec. 31, 2016
Acquired Intangible Assets [Line Items]
Weighted-average useful life (years)		3 years 8 months	2 years 9 months 12 days
User base
Acquired Intangible Assets [Line Items]
Weighted-average useful life (years)		1 year 1 month	3 years 8 months
Angie's List
Acquired Intangible Assets [Line Items]
Total identifiable intangible assets acquired	$ 317,300
Angie's List | Service providers
Acquired Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 90,500
Weighted-average useful life (years)	3 years
Angie's List | Developed technology
Acquired Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 63,900
Weighted-average useful life (years)	6 years
Angie's List | Memberships
Acquired Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 15,900
Weighted-average useful life (years)	3 years
Angie's List | User base
Acquired Intangible Assets [Line Items]
Finite-lived intangible assets acquired	$ 10,000
Weighted-average useful life (years)	1 year
Angie's List | Indefinite-lived trade names and trademarks
Acquired Intangible Assets [Line Items]
Indefinite-lived intangible assets acquired	$ 137,000

BUSINESS COMBINATION - Pro Form

BUSINESS COMBINATION - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Business Combinations [Abstract]
Revenue	$ 898,584	$ 838,834	$ 2,571,613	$ 2,544,019
Net earnings (loss) attributable to IAC shareholders	$ 244,400	$ 12,237	$ 313,054	$ (221,446)
Basic earnings (loss) per share attributable to IAC shareholders (in dollars per share)	$ 3.02	$ 0.15	$ 3.94	$ (2.76)
Diluted earnings (loss) per share attributable to IAC shareholders (in dollars per share)	$ 2.80	$ 0.15	$ 3.70	$ (2.76)
Modification of Equity Awards
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma adjustments, stock-based compensation increase (reduction)	$ (85,100)	$ 19,700	$ (52,800)	$ 51,400
One-Time Acquisition-related Costs
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma adjustments, transaction-related costs reduction	22,100		25,600
Severance and retention costs included in transaction-related costs	12,000		12,000
Amortization Adjustment
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma adjustments, amortization of intangible assets increase	$ 11,400	14,000	$ 34,400	42,100
Deferred Revenue Write-off
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma adjustments, revenue reduction		$ 5,000		$ 31,400

GOODWILL AND INTANGIBLE ASSET43

GOODWILL AND INTANGIBLE ASSETS - Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 2,501,589	$ 1,924,052	$ 2,245,364
Intangible assets with indefinite lives	460,333	320,645
Intangible assets with definite lives, net	199,770	34,806
Total goodwill and intangible assets, net	$ 3,161,692	$ 2,279,503

GOODWILL AND INTANGIBLE ASSET44

GOODWILL AND INTANGIBLE ASSETS - Goodwill by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance				$ 1,924,052	$ 2,245,364	$ 2,245,364
Additions				600,519		32,237
(Deductions)				(74,430)		(67,811)
Impairment	$ 0	$ 0		0	(275,367)	(275,367)
Foreign Exchange Translation				51,448		(10,371)
Goodwill, ending balance	2,501,589			2,501,589		1,924,052
Match Group
Goodwill [Roll Forward]
Goodwill, beginning balance				1,206,538	1,218,607	1,218,607
Additions				255		603
(Deductions)				0		(2,983)
Impairment						0
Foreign Exchange Translation				43,575		(9,689)
Goodwill, ending balance	1,250,368			1,250,368		1,206,538
Match Group | Operating segments
Goodwill [Roll Forward]
Impairment					0
ANGI Homeservices
Goodwill [Roll Forward]
Goodwill, beginning balance				170,611	150,251	150,251
Additions				593,880		21,985
(Deductions)				0		0
Impairment						0
Foreign Exchange Translation				7,865		(1,625)
Goodwill, ending balance	772,356			772,356		170,611
ANGI Homeservices | Operating segments
Goodwill [Roll Forward]
Impairment					0
Video
Goodwill [Roll Forward]
Goodwill, beginning balance				25,239	15,590	15,590
Additions				6,384		9,649
(Deductions)				0		0
Impairment						0
Foreign Exchange Translation				0		0
Goodwill, ending balance	31,623			31,623		25,239
Video | Operating segments
Goodwill [Roll Forward]
Impairment					0
Goodwill, accumulated impairment loss	11,600			11,600		11,600
Applications
Goodwill [Roll Forward]
Goodwill, beginning balance				447,242	447,242	447,242
Additions				0		0
(Deductions)				0		0
Impairment						0
Foreign Exchange Translation				0		0
Goodwill, ending balance	447,242			447,242		447,242
Applications | Operating segments
Goodwill [Roll Forward]
Impairment					0
Goodwill, accumulated impairment loss	529,100			529,100		529,100
Publishing
Goodwill [Roll Forward]
Goodwill, beginning balance				0	277,192	277,192
Additions						0
(Deductions)						(1,968)
Impairment						(275,367)
Foreign Exchange Translation						143
Goodwill, ending balance						0
Publishing | Operating segments
Goodwill [Roll Forward]
Impairment			$ (275,400)		(275,367)
Goodwill, accumulated impairment loss	598,000			598,000		598,000
Other
Goodwill [Roll Forward]
Goodwill, beginning balance				74,422	136,482	136,482
Additions				0		0
(Deductions)				(74,430)		(62,860)
Impairment						0
Foreign Exchange Translation				8		800
Goodwill, ending balance	$ 0			$ 0		$ 74,422
Other | Operating segments
Goodwill [Roll Forward]
Impairment					$ 0

GOODWILL AND INTANGIBLE ASSET45

GOODWILL AND INTANGIBLE ASSETS - Definite-lived Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 257,334	$ 136,974
Accumulated Amortization	(57,564)	(102,168)
Definite-lived intangible assets, net	$ 199,770	$ 34,806
Weighted-average useful life (years)	3 years 8 months	2 years 9 months 12 days
Advertiser and supplier relationships and other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 119,029	$ 7,230
Accumulated Amortization	(4,654)	(2,612)
Definite-lived intangible assets, net	$ 114,375	$ 4,618
Weighted-average useful life (years)	3 years	4 years 6 months
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 104,876	$ 38,602
Accumulated Amortization	(32,348)	(27,667)
Definite-lived intangible assets, net	$ 72,528	$ 10,935
Weighted-average useful life (years)	4 years 11 months	3 years 5 months
Customer lists and user base
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 13,911	$ 12,485
Accumulated Amortization	(2,973)	(9,997)
Definite-lived intangible assets, net	$ 10,938	$ 2,488
Weighted-average useful life (years)	1 year 1 month	3 years 8 months
Content
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 5,000	$ 14,802
Accumulated Amortization	(3,723)	(8,965)
Definite-lived intangible assets, net	$ 1,277	$ 5,837
Weighted-average useful life (years)	5 years	4 years 4 months
Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 14,518	$ 63,855
Accumulated Amortization	(13,866)	(52,927)
Definite-lived intangible assets, net	$ 652	$ 10,928
Weighted-average useful life (years)	2 years 8 months	1 year 9 months 12 days

GOODWILL AND INTANGIBLE ASSET46

GOODWILL AND INTANGIBLE ASSETS - Estimated Future Amortization (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,018	$ 68,567
2,019	51,422
2,020	47,775
2,021	10,735
2,022	10,650
Thereafter	10,621
Definite-lived intangible assets, net	$ 199,770	$ 34,806

FAIR VALUE MEASUREMENTS AND F47

FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Fair Value on a Recurring Basis - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets:
Total	$ 978,970	$ 984,635
Liabilities:
Contingent consideration arrangements	(1,792)	(33,871)
Money market funds
Assets:
Cash equivalents	865,630	667,662
Commercial paper
Assets:
Cash equivalents		123,640
Time deposits
Assets:
Cash equivalents	105,942	79,000
Treasury discount notes
Assets:
Cash equivalents	1,199	24,991
Marketable securities		34,974
Commercial paper
Assets:
Marketable securities		49,797
Corporate debt securities
Assets:
Marketable securities		4,571
Certificates of deposit
Assets:
Cash equivalents	6,199
Quoted Market Prices in Active Markets for Identical Assets (Level 1)
Assets:
Total	866,829	727,627
Liabilities:
Contingent consideration arrangements	0	0
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Assets:
Cash equivalents	865,630	667,662
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Commercial paper
Assets:
Cash equivalents		0
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Time deposits
Assets:
Cash equivalents	0	0
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Treasury discount notes
Assets:
Cash equivalents	1,199	24,991
Marketable securities		34,974
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Commercial paper
Assets:
Marketable securities		0
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities
Assets:
Marketable securities		0
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Certificates of deposit
Assets:
Cash equivalents	0
Significant Other Observable Inputs (Level 2)
Assets:
Total	112,141	257,008
Liabilities:
Contingent consideration arrangements	0	0
Significant Other Observable Inputs (Level 2) | Money market funds
Assets:
Cash equivalents	0	0
Significant Other Observable Inputs (Level 2) | Commercial paper
Assets:
Cash equivalents		123,640
Significant Other Observable Inputs (Level 2) | Time deposits
Assets:
Cash equivalents	105,942	79,000
Significant Other Observable Inputs (Level 2) | Treasury discount notes
Assets:
Cash equivalents	0	0
Marketable securities		0
Significant Other Observable Inputs (Level 2) | Commercial paper
Assets:
Marketable securities		49,797
Significant Other Observable Inputs (Level 2) | Corporate debt securities
Assets:
Marketable securities		4,571
Significant Other Observable Inputs (Level 2) | Certificates of deposit
Assets:
Cash equivalents	6,199
Significant Unobservable Inputs (Level 3)
Assets:
Total	0	0
Liabilities:
Contingent consideration arrangements	(1,792)	(33,871)
Significant Unobservable Inputs (Level 3) | Money market funds
Assets:
Cash equivalents	0	0
Significant Unobservable Inputs (Level 3) | Commercial paper
Assets:
Cash equivalents		0
Significant Unobservable Inputs (Level 3) | Time deposits
Assets:
Cash equivalents	0	0
Significant Unobservable Inputs (Level 3) | Treasury discount notes
Assets:
Cash equivalents	0	0
Marketable securities		0
Significant Unobservable Inputs (Level 3) | Commercial paper
Assets:
Marketable securities		0
Significant Unobservable Inputs (Level 3) | Corporate debt securities
Assets:
Marketable securities		$ 0
Significant Unobservable Inputs (Level 3) | Certificates of deposit
Assets:
Cash equivalents	$ 0

FAIR VALUE MEASUREMENTS AND F48

FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Schedule of Changes in Level 3 Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Contingent Consideration Arrangements
Contingent Consideration Arrangements
Balance at beginning of period	$ (24,829)	$ (45,526)	$ (33,871)	$ (33,873)
Fair value adjustments	(60)	2,477	(4,945)	(7,993)
Included in other comprehensive (loss) income	(332)	(333)	(1,405)	(5,614)
Fair value at date of acquisition			0	1,948
Settlements	23,429	30	38,429	2,180
Proceeds from sale			0	0
Balance at end of period	$ (1,792)	(43,352)	$ (1,792)	(43,352)
Auction Rate Security
Auction Rate Security
Balance at beginning of period				4,050
Fair value adjustments				0
Included in other comprehensive (loss) income				5,950
Fair value at date of acquisition				0
Settlements				0
Proceeds from sale				(10,000)
Balance at end of period		$ 0		$ 0

FAIR VALUE MEASUREMENTS AND F49

FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Narrative (Details) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017USD ($)arrangement	Dec. 31, 2016USD ($)
Contingent Consideration Arrangements
Number of contingent consideration arrangements related to business acquisitions | arrangement	1
Contingent consideration, maximum amount at balance sheet date	$ 3
Contingent consideration, fair value at balance sheet date with a maximum limit	2.1
Contingent consideration, at fair value, current	0.6	$ 33.4
Contingent consideration, at fair value, noncurrent	1.2	0.4
Assets measured at fair value on a nonrecurring basis
Cost method investments	$ 116.2	$ 116.1
Contingent Consideration Arrangements
Contingent Consideration Arrangements
Contingent consideration, discount rates	12.00%	12.00%

FAIR VALUE MEASUREMENTS AND F50

FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Carrying Value and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of long-term debt	$ 0	$ (20,000)
Long-term debt, net of current portion	(1,649,267)	(1,582,484)
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of long-term debt	0	(20,000)
Long-term debt, net of current portion	(1,649,267)	(1,582,484)
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Current portion of long-term debt	0	(20,311)
Long-term debt, net of current portion	$ (1,720,311)	$ (1,657,861)

LONG-TERM DEBT - Schedule of Lo

LONG-TERM DEBT - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Aug. 14, 2017	Dec. 31, 2016	Dec. 08, 2016	Sep. 30, 2016
Debt Instrument [Line Items]
Less: Current portion of long-term debt	$ 0		$ 20,000
Long-term debt, net of current portion	$ 1,649,267		1,582,484
Senior Notes | 6.75% Senior Notes due December 15, 2022 (the Match Group 6.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2016
Debt Instrument [Line Items]
Stated interest rate (as a percent)	6.75%
Senior Notes | 6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes); interest payable each June 1 and December 1, which commenced December 1, 2016
Debt Instrument [Line Items]
Stated interest rate (as a percent)	6.375%				6.375%
Senior Notes | 4.875% Senior Notes due November 30, 2018 (the 4.875% Senior Notes); interest payable each May 30 and November 30, which commenced May 30, 2014
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.875%				4.875%
Senior Notes | 4.75% Senior Notes due December 15, 2022 (the 4.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2013
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.75%				4.75%
IAC
Debt Instrument [Line Items]
Long-term debt	$ 396,733		428,323
Less: Current portion of long-term debt	0		20,000
Less: Unamortized debt issuance costs	1,464		2,332
Long-term debt, net of current portion	395,269		405,991
IAC | Senior Notes | 4.875% Senior Notes due November 30, 2018 (the 4.875% Senior Notes); interest payable each May 30 and November 30, which commenced May 30, 2014
Debt Instrument [Line Items]
Long-term debt	361,874		390,214
IAC | Senior Notes | 4.75% Senior Notes due December 15, 2022 (the 4.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2013
Debt Instrument [Line Items]
Long-term debt	34,859		38,109
Match Group, Inc.
Debt Instrument [Line Items]
Long-term debt	1,270,172		1,195,172
Less: Unamortized original issue discount and original issue premium, net	4,470		5,245
Less: Unamortized debt issuance costs	11,704		13,434
Long-term debt, net of current portion	1,253,998		1,176,493
Match Group, Inc. | Senior Notes | 6.75% Senior Notes due December 15, 2022 (the Match Group 6.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2016
Debt Instrument [Line Items]
Long-term debt	445,172		445,172
Match Group, Inc. | Senior Notes | 6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes); interest payable each June 1 and December 1, which commenced December 1, 2016
Debt Instrument [Line Items]
Long-term debt	400,000		400,000
Match Group, Inc. | Term Loan | Match Group Term Loan due November 16, 2022
Debt Instrument [Line Items]
Long-term debt	$ 425,000	$ 425,000	$ 350,000	$ 350,000
Number of days prior to maturity date	91 days

LONG-TERM DEBT - Narrative (Det

LONG-TERM DEBT - Narrative (Details)	Oct. 02, 2017USD ($)	Aug. 14, 2017USD ($)	Dec. 08, 2016USD ($)	Jun. 01, 2016USD ($)	Mar. 31, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)	Nov. 16, 2015USD ($)
Debt Instrument [Line Items]
Proceeds from Match Group Term Loan						$ 75,000,000	$ 0
Repurchase and redemption of Senior Notes						31,590,000	126,271,000
IAC
Debt Instrument [Line Items]
Debt instrument, outstanding balance						396,733,000		$ 428,323,000
Proceeds from Match Group Term Loan						0
Repurchase and redemption of Senior Notes						31,590,000	$ 126,271,000
Match Group, Inc.
Debt Instrument [Line Items]
Debt instrument, outstanding balance						$ 1,270,172,000		1,195,172,000
Senior Notes | 6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes); interest payable each June 1 and December 1, which commenced December 1, 2016
Debt Instrument [Line Items]
Stated interest rate (as a percent)						6.375%	6.375%
Senior Notes | 6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes); interest payable each June 1 and December 1, which commenced December 1, 2016 | Match Group, Inc.
Debt Instrument [Line Items]
Debt instrument, face amount				$ 400,000,000
Debt instrument, outstanding balance						$ 400,000,000		400,000,000
Senior Notes | 6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes); interest payable each June 1 and December 1, which commenced December 1, 2016 | Maximum
Debt Instrument [Line Items]
Maximum leverage ratio						5
Senior Notes | 6.75% Senior Notes due December 15, 2022 (the Match Group 6.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2016
Debt Instrument [Line Items]
Stated interest rate (as a percent)						6.75%
Senior Notes | 6.75% Senior Notes due December 15, 2022 (the Match Group 6.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2016 | Match Group, Inc.
Debt Instrument [Line Items]
Debt instrument, outstanding balance						$ 445,172,000		445,172,000
Senior Notes | 4.875% Senior Notes due November 30, 2018 (the 4.875% Senior Notes); interest payable each May 30 and November 30, which commenced May 30, 2014
Debt Instrument [Line Items]
Stated interest rate (as a percent)						4.875%	4.875%
Senior Notes | 4.875% Senior Notes due November 30, 2018 (the 4.875% Senior Notes); interest payable each May 30 and November 30, which commenced May 30, 2014 | IAC
Debt Instrument [Line Items]
Debt instrument, outstanding balance						$ 361,874,000		390,214,000
Repurchase and redemption of Senior Notes						$ 28,300,000	$ 109,800,000
Senior Notes | 4.75% Senior Notes due December 15, 2022 (the 4.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2013
Debt Instrument [Line Items]
Stated interest rate (as a percent)						4.75%	4.75%
Senior Notes | 4.75% Senior Notes due December 15, 2022 (the 4.75% Senior Notes); interest payable each June 15 and December 15, which commenced June 15, 2013 | IAC
Debt Instrument [Line Items]
Debt instrument, outstanding balance						$ 34,859,000		38,109,000
Repurchase and redemption of Senior Notes						3,300,000	$ 16,500,000
Term Loan | Match Group Term Loan due November 16, 2022 | Match Group, Inc.
Debt Instrument [Line Items]
Debt instrument, face amount									$ 800,000,000
Repayment of debt			$ 40,000,000	$ 400,000,000	$ 10,000,000		$ 400,000,000
Debt instrument, outstanding balance		$ 425,000,000	$ 350,000,000			$ 425,000,000		350,000,000
Proceeds from Match Group Term Loan		$ 75,000,000
Debt instrument, interest rate						3.81%
Term Loan | Match Group Term Loan due November 16, 2022 | LIBOR | Match Group, Inc.
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)		2.50%
Term Loan | Match Group Term Loan due November 16, 2022 | LIBOR | Minimum | Match Group, Inc.
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)		0.00%
Revolving Credit Facility | Match Group Credit Agreement | Match Group, Inc.
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 500,000,000
Credit facility, borrowings outstanding						$ 0		0
Annual commitment fee on undrawn funds, basis points						0.30%
Revolving Credit Facility | Match Group Credit Agreement | Maximum | Match Group, Inc.
Debt Instrument [Line Items]
Maximum leverage ratio						5
Revolving Credit Facility | Match Group Credit Agreement | Minimum | Match Group, Inc.
Debt Instrument [Line Items]
Minimum interest coverage ratio						2.5
Revolving Credit Facility | IAC Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 300,000,000
Credit facility, borrowings outstanding						$ 0		$ 0
Annual commitment fee on undrawn funds, basis points						0.35%
Revolving Credit Facility | IAC Credit Facility | Maximum
Debt Instrument [Line Items]
Maximum leverage ratio						3.25
Subsequent Event | Senior Notes | 4.875% Senior Notes due November 30, 2018 (the 4.875% Senior Notes); interest payable each May 30 and November 30, which commenced May 30, 2014
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.875%
Repurchase and redemption of Senior Notes	$ 361,900,000
Subsequent Event | Senior Notes | 4.875% Senior Notes due November 30, 2018 (the 4.875% Senior Notes); interest payable each May 30 and November 30, which commenced May 30, 2014 | IAC
Debt Instrument [Line Items]
Repurchase and redemption of Senior Notes	361,900,000
Subsequent Event | Senior Notes | 0.875% Exchangeable Senior Notes due October 1, 2022 | Subsidiary
Debt Instrument [Line Items]
Debt instrument, face amount	$ 517,500,000
Stated interest rate (as a percent)	0.875%

ACCUMULATED OTHER COMPREHENSI53

ACCUMULATED OTHER COMPREHENSIVE LOSS - Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ 2,010,670
Other comprehensive income (loss) before reclassifications, net of tax	$ 37,225	$ (5,018)	69,958	$ 1,330
Amounts reclassified to earnings	0	(259)	(3,348)	6,958
Net currernt period other comprehensive income (loss)	37,225	(5,277)	66,610	8,288
Reallocation of accumulated other comprehensive loss (income) related to the noncontrolling interests created in the Match Group initial public offering				21,131
Ending balance	2,908,703		2,908,703
Other comprehensive income (loss), unrealized holding gain (loss) on available-for-sale securities, tax provision (benefit)		100		(700)
Tax provision (benefit) on amounts reclassified to earnings		200	(3,800)	200
Tax provision (benefit) on accumulated other comprehensive income	0		0
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(136,738)	(121,612)	(170,149)	(154,645)
Other comprehensive income (loss) before reclassifications, net of tax	37,225	(5,132)	69,951	(3,538)
Amounts reclassified to earnings	0	0	685	9,850
Net currernt period other comprehensive income (loss)	37,225	(5,132)	70,636	6,312
Reallocation of accumulated other comprehensive loss (income) related to the noncontrolling interests created in the Match Group initial public offering				21,589
Ending balance	(99,513)	(126,744)	(99,513)	(126,744)
Unrealized Gains (Losses) On Available-For-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	0	4,205	4,026	2,542
Other comprehensive income (loss) before reclassifications, net of tax	0	114	7	4,868
Amounts reclassified to earnings	0	(259)	(4,033)	(2,892)
Net currernt period other comprehensive income (loss)	0	(145)	(4,026)	1,976
Reallocation of accumulated other comprehensive loss (income) related to the noncontrolling interests created in the Match Group initial public offering				(458)
Ending balance	0	4,060	0	4,060
Accumulated Other Comprehensive (Loss) Income
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(136,738)	(117,407)	(166,123)	(152,103)
Ending balance	$ (99,513)	$ (122,684)	$ (99,513)	$ (122,684)

EARNINGS (LOSS) PER SHARE - Com

EARNINGS (LOSS) PER SHARE - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerator: Basic
Net earnings (loss)	$ 225,639	$ 52,340	$ 334,659	$ (130,268)
Net earnings attributable to noncontrolling interests	(45,996)	(9,178)	(62,539)	(13,063)
Net earnings (loss) attributable to IAC shareholders	179,643	43,162	272,120	(143,331)
Numerator: Diluted
Net earnings (loss)	225,639	52,340	334,659	(130,268)
Net earnings attributable to noncontrolling interests	(45,996)	(9,178)	(62,539)	(13,063)
Impact from public subsidiaries' dilutive securities	(23,749)	(3,473)	(34,104)	0
Net earnings (loss) attributable to IAC shareholders	$ 155,894	$ 39,689	$ 238,016	$ (143,331)
Denominator: Basic
Weighted average basic shares outstanding (in shares)	80,817	79,532	79,369	80,357
Denominator: Diluted
Weighted average basic shares outstanding (in shares)	80,817	79,532	79,369	80,357
Dilutive securities including stock options and RSUs and subsidiary denominated equity awards (in shares)	6,379	2,087	5,133	0
Denominator for earnings per share - weighted average shares (in shares)	87,196	81,619	84,502	80,357
Earnings (loss) per share attributable to IAC shareholders: Basic
Basic earnings (loss) per share (in dollars per share)	$ 2.22	$ 0.54	$ 3.43	$ (1.78)
Earnings (loss) per share attributable to IAC shareholders: Diluted
Diluted earnings (loss) per share (in dollars per share)	$ 1.79	$ 0.49	$ 2.82	$ (1.78)

EARNINGS (LOSS) PER SHARE - Ant

EARNINGS (LOSS) PER SHARE - Antidilutive Securities (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Anti-dilutive weighted average common shares
Potentially dilutive securities excluded from calculation of diluted earnings per share (less than or equal to) (in shares)				9.8
Subsidiary Denominated Equity, Stock Options, and RSUs
Anti-dilutive weighted average common shares
Potentially dilutive securities excluded from calculation of diluted earnings per share (less than or equal to) (in shares)	0	3.3	0.1
Market-based awards and PSUs
Anti-dilutive weighted average common shares
Potentially dilutive securities excluded from calculation of diluted earnings per share (less than or equal to) (in shares)	0.3	0.3	0.3

SEGMENT INFORMATION - Financial

SEGMENT INFORMATION - Financial Data by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenue	$ 828,434	$ 764,102	$ 2,356,654	$ 2,328,720
Operating income (loss)	(18,589)	85,584	94,106	(145,445)
Adjusted EBITDA	137,571	138,986	384,054	336,908
Operating segments | Match Group
Segment Reporting Information [Line Items]
Revenue	343,418	287,530	951,754	823,240
Operating income (loss)	91,008	90,938	232,854	202,624
Adjusted EBITDA	119,564	107,101	315,705	275,834
Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Revenue	181,717	133,560	513,173	375,222
Operating income (loss)	(112,505)	10,148	(115,258)	19,147
Adjusted EBITDA	(2,266)	15,291	21,612	33,927
Operating segments | Video
Segment Reporting Information [Line Items]
Revenue	78,338	59,955	184,097	162,361
Operating income (loss)	(1,809)	(2,663)	(25,227)	(25,187)
Adjusted EBITDA	(822)	(894)	(22,386)	(21,770)
Operating segments | Applications
Segment Reporting Information [Line Items]
Revenue	136,333	142,782	439,199	445,735
Operating income (loss)	29,386	29,240	101,288	75,839
Adjusted EBITDA	31,077	34,575	106,556	94,715
Operating segments | Publishing
Segment Reporting Information [Line Items]
Revenue	88,755	74,902	244,959	326,195
Operating income (loss)	5,677	(14,562)	(2,968)	(324,720)
Adjusted EBITDA	7,088	(6,208)	11,007	(6,639)
Operating segments | Other
Segment Reporting Information [Line Items]
Revenue		65,515	23,980	196,323
Operating income (loss)	0	(695)	(5,621)	(11,313)
Adjusted EBITDA	0	2,783	(1,532)	(1,129)
Inter-segment eliminations
Segment Reporting Information [Line Items]
Revenue	(127)	(142)	(508)	(356)
Corporate
Segment Reporting Information [Line Items]
Operating income (loss)	(30,346)	(26,822)	(90,962)	(81,835)
Adjusted EBITDA	$ (17,070)	$ (13,662)	$ (46,908)	$ (38,030)

SEGMENT INFORMATION - Schedule

SEGMENT INFORMATION - Schedule of Revenue Disaggregated by Service (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenue	$ 828,434	$ 764,102	$ 2,356,654	$ 2,328,720
Operating segments | Match Group
Segment Reporting Information [Line Items]
Direct revenue	330,098	273,727	917,273	786,176
Indirect revenue (principally advertising revenue)	13,320	13,803	34,481	37,064
Revenue	343,418	287,530	951,754	823,240
Operating segments | ANGI Homeservices
Segment Reporting Information [Line Items]
Consumer connection revenue	151,056	110,874	427,854	310,962
Membership subscription revenue	22,146	14,083	61,145	40,008
Other	8,515	8,603	24,174	24,252
Revenue	181,717	133,560	513,173	375,222
Operating segments | Applications
Segment Reporting Information [Line Items]
Advertising	121,425	129,027	390,160	409,212
Subscription (including downloadable app fees) and other	14,908	13,755	49,039	36,523
Revenue	136,333	142,782	439,199	445,735
Operating segments | Publishing
Segment Reporting Information [Line Items]
Advertising	87,788	74,272	242,957	324,422
Other	967	630	2,002	1,773
Revenue	$ 88,755	$ 74,902	$ 244,959	$ 326,195

SEGMENT INFORMATION - Schedul58

SEGMENT INFORMATION - Schedule of Geographic Information About Revenue and Long-Lived Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Revenue and long-lived assets by geography
Revenue	$ 828,434	$ 764,102	$ 2,356,654	$ 2,328,720
Long-lived assets (excluding goodwill and intangible assets)	320,277		320,277		$ 306,248
United States
Revenue and long-lived assets by geography
Revenue	577,362	567,132	1,670,980	1,721,348
Long-lived assets (excluding goodwill and intangible assets)	293,005		293,005		281,725
All Other Countries
Revenue and long-lived assets by geography
Revenue	251,072	$ 196,970	685,674	$ 607,372
Long-lived assets (excluding goodwill and intangible assets)	$ 27,272		$ 27,272		$ 24,523

SEGMENT INFORMATION - Schedul59

SEGMENT INFORMATION - Schedule of Reconciliation of Operating Income (Loss) to Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	$ (18,589)	$ 85,584		$ 94,106	$ (145,445)
Stock-based compensation expense	134,472	23,661		207,362	82,610
Depreciation	17,263	17,951		55,490	51,321
Amortization of intangibles	4,366	14,267		22,151	65,062
Acquisition-related Contingent Consideration Fair Value Adjustments	59	(2,477)		4,945	7,993
Goodwill impairment	0	0		0	275,367	$ 275,367
Adjusted EBITDA	137,571	138,986		384,054	336,908
Interest expense	(25,036)	(27,118)		(74,556)	(82,622)
Other (expense) income, net	(10,216)	11,700		(7,700)	20,405
(Loss) earnings before income taxes	(53,841)	70,166		11,850	(207,662)
Income tax benefit (provision)	279,480	(17,826)		322,809	77,394
Net earnings (loss)	225,639	52,340		334,659	(130,268)
Net earnings attributable to noncontrolling interests	(45,996)	(9,178)		(62,539)	(13,063)
Net earnings (loss) attributable to IAC shareholders	179,643	43,162		272,120	(143,331)
Match Group
Segment Reporting, Other Significant Reconciling Item [Line Items]
Goodwill impairment						0
ANGI Homeservices
Segment Reporting, Other Significant Reconciling Item [Line Items]
Goodwill impairment						0
Video
Segment Reporting, Other Significant Reconciling Item [Line Items]
Goodwill impairment						0
Applications
Segment Reporting, Other Significant Reconciling Item [Line Items]
Goodwill impairment						0
Publishing
Segment Reporting, Other Significant Reconciling Item [Line Items]
Goodwill impairment						275,367
Other
Segment Reporting, Other Significant Reconciling Item [Line Items]
Goodwill impairment						$ 0
Operating segments | Match Group
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	91,008	90,938		232,854	202,624
Stock-based compensation expense	19,949	10,718		53,627	40,810
Depreciation	8,147	7,192		23,619	20,119
Amortization of intangibles	401	3,382		1,208	15,004
Acquisition-related Contingent Consideration Fair Value Adjustments	59	(5,129)		4,397	(2,723)
Goodwill impairment					0
Adjusted EBITDA	119,564	107,101		315,705	275,834
Operating segments | ANGI Homeservices
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	(112,505)	10,148		(115,258)	19,147
Stock-based compensation expense	103,980	2,391		120,280	6,685
Depreciation	3,491	2,026		9,705	5,824
Amortization of intangibles	2,768	726		6,885	2,271
Acquisition-related Contingent Consideration Fair Value Adjustments	0	0		0	0
Goodwill impairment					0
Adjusted EBITDA	(2,266)	15,291		21,612	33,927
Operating segments | Video
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	(1,809)	(2,663)		(25,227)	(25,187)
Stock-based compensation expense	134	640		267	640
Depreciation	541	438		1,637	1,313
Amortization of intangibles	312	691		937	1,656
Acquisition-related Contingent Consideration Fair Value Adjustments	0	0		0	(192)
Goodwill impairment					0
Adjusted EBITDA	(822)	(894)		(22,386)	(21,770)
Operating segments | Applications
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	29,386	29,240		101,288	75,839
Stock-based compensation expense	0	0		0	0
Depreciation	1,155	1,073		3,087	3,304
Amortization of intangibles	536	1,519		1,633	4,573
Acquisition-related Contingent Consideration Fair Value Adjustments	0	2,743		548	10,999
Goodwill impairment					0
Adjusted EBITDA	31,077	34,575		106,556	94,715
Operating segments | Publishing
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	5,677	(14,562)		(2,968)	(324,720)
Stock-based compensation expense	0	0		0	0
Depreciation	1,062	2,029		4,011	6,366
Amortization of intangibles	349	6,325		9,964	36,348
Acquisition-related Contingent Consideration Fair Value Adjustments	0	0		0	0
Goodwill impairment			$ 275,400		275,367
Adjusted EBITDA	7,088	(6,208)		11,007	(6,639)
Operating segments | Other
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	0	(695)		(5,621)	(11,313)
Stock-based compensation expense	0	427		1,729	531
Depreciation		1,518		836	4,534
Amortization of intangibles	0	1,624		1,524	5,210
Acquisition-related Contingent Consideration Fair Value Adjustments	0	(91)		0	(91)
Goodwill impairment					0
Adjusted EBITDA	0	2,783		(1,532)	(1,129)
Corporate
Segment Reporting, Other Significant Reconciling Item [Line Items]
Operating (loss) income	(30,346)	(26,822)		(90,962)	(81,835)
Stock-based compensation expense	10,409	9,485		31,459	33,944
Depreciation	2,867	3,675		12,595	9,861
Amortization of intangibles	0	0		0	0
Acquisition-related Contingent Consideration Fair Value Adjustments	0	0		0	0
Goodwill impairment					0
Adjusted EBITDA	$ (17,070)	$ (13,662)		$ (46,908)	$ (38,030)

CONSOLIDATED FINANCIAL STATEM60

CONSOLIDATED FINANCIAL STATEMENT DETAILS - Other Income (Expense) (Details) - USD ($) $ in Thousands	Dec. 08, 2016	Jun. 01, 2016	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Additional Consolidated Financial Statement Details [Line Items]
Other (expense) income, net				$ (10,216)	$ 11,700	$ (7,700)	$ 20,405
Other Income (Expense)
Additional Consolidated Financial Statement Details [Line Items]
Foreign currency exchange gain (loss)				(10,200)	10,900	(16,300)	24,000
Other-than-temporary impairment on cost method investments				2,900	1,800	7,700	4,500
Gain (loss) on mark-to-market adjustment related to a subsidiary denominated equity award issued to a non-employee				(1,500)	900	(12,200)	(2,500)
Expense related to repricing of debt				2,100		2,100
Gain on sale of long-term investments				4,500		25,800	3,500
Interest income				$ 2,900	$ 1,100	7,100	3,800
Write off of original discount and deferred financing costs							11,100
Other Income (Expense) | Senior Notes
Additional Consolidated Financial Statement Details [Line Items]
Loss on redemption of senior notes							3,200
Disposal Group, Disposed of by Sale, Not Discontinued Operations | The Princeton Review | Other Income (Expense)
Additional Consolidated Financial Statement Details [Line Items]
Gain (loss) related to sale of business						$ (1,200)
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PriceRunner | Other Income (Expense)
Additional Consolidated Financial Statement Details [Line Items]
Gain (loss) related to sale of business							12,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | ASKfm | Other Income (Expense)
Additional Consolidated Financial Statement Details [Line Items]
Gain (loss) related to sale of business							(3,800)
Match Group Term Loan due November 16, 2022 | Match Group, Inc. | Term Loan
Additional Consolidated Financial Statement Details [Line Items]
Repayment of debt	$ 40,000	$ 400,000	$ 10,000				$ 400,000
4.75% Senior Notes due December 15, 2022 | Senior Notes
Additional Consolidated Financial Statement Details [Line Items]
Stated interest rate (as a percent)				4.75%	4.75%	4.75%	4.75%
4.875% Senior Notes due November 30, 2018 | Senior Notes
Additional Consolidated Financial Statement Details [Line Items]
Stated interest rate (as a percent)				4.875%	4.875%	4.875%	4.875%

RELATED PARTY TRANSACTION - Nar

RELATED PARTY TRANSACTION - Narrative (Details) - ANGI Homeservices $ in Millions	Sep. 29, 2017USD ($)intercompany_note
Intercompany Notes [Member]
Related Party Transaction [Line Items]
Number of intercompany notes | intercompany_note	2
Payoff Intercompany Note
Related Party Transaction [Line Items]
Notes receivable due from related party	$ 61.5
Working Capital Intercompany Note
Related Party Transaction [Line Items]
Notes receivable due from related party	$ 15

GUARANTOR AND NON-GUARANTOR F62

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Narrative (Details) - Senior Notes	Sep. 30, 2017	Sep. 30, 2016
4.875% Senior Notes due November 30, 2018
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.875%	4.875%
4.75% Senior Notes due December 15, 2022
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.75%	4.75%
6.375% Senior Notes due June 1, 2024 (the Match Group 6.375% Senior Notes)
Debt Instrument [Line Items]
Stated interest rate (as a percent)	6.375%	6.375%

GUARANTOR AND NON-GUARANTOR F63

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
ASSETS
Cash and cash equivalents	$ 1,255,317	$ 1,329,187	$ 1,189,784	$ 1,481,447
Marketable securities	0	89,342
Accounts receivable, net	271,209	220,138
Other current assets	200,377	204,068
Intercompany receivables	0	0
Property and equipment, net	320,277	306,248
Goodwill	2,501,589	1,924,052		2,245,364
Intangible assets, net	660,103	355,451
Investment in subsidiaries	0	0
Other non-current assets	332,083	217,387
TOTAL ASSETS	5,540,955	4,645,873
LIABILITIES AND SHAREHOLDERS' EQUITY
Current portion of long-term debt	0	20,000
Accounts payable	104,806	62,863
Other current liabilities	730,720	630,525
Long-term debt, net of current portion	1,649,267	1,582,484
Income taxes payable	33,290	33,528
Intercompany liabilities	0	0
Other long-term liabilities	73,188	272,976
Redeemable noncontrolling interests	40,981	32,827
IAC shareholders' equity	2,428,921	1,869,222
Noncontrolling interests	479,782	141,448
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	5,540,955	4,645,873
IAC
ASSETS
Cash and cash equivalents	501,918	553,643	521,474	1,074,658
Marketable securities		89,342
Accounts receivable, net	0	0
Other current assets	59,319	71,152
Intercompany receivables	0	0
Property and equipment, net	3,163	4,350
Goodwill	0	0
Intangible assets, net	0	0
Investment in subsidiaries	4,489,006	3,659,570
Other non-current assets	50,991	52,228
TOTAL ASSETS	5,104,397	4,430,285
LIABILITIES AND SHAREHOLDERS' EQUITY
Current portion of long-term debt	0	20,000
Accounts payable	2,521	2,697
Other current liabilities	50,523	42,441
Long-term debt, net of current portion	395,269	405,991
Income taxes payable	11	0
Intercompany liabilities	2,035,153	1,774,520
Other long-term liabilities	191,999	315,414
Redeemable noncontrolling interests	0	0
IAC shareholders' equity	2,428,921	1,869,222
Noncontrolling interests	0	0
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	5,104,397	4,430,285
Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	0	0	0	0
Marketable securities		0
Accounts receivable, net	81,448	77,335
Other current assets	21,305	36,154
Intercompany receivables	754,376	650,595
Property and equipment, net	160,968	159,304
Goodwill	412,010	412,010
Intangible assets, net	75,627	83,179
Investment in subsidiaries	549,342	523,814
Other non-current assets	115,668	115,150
TOTAL ASSETS	2,170,744	2,057,541
LIABILITIES AND SHAREHOLDERS' EQUITY
Current portion of long-term debt		0
Accounts payable	23,806	29,867
Other current liabilities	69,445	84,629
Long-term debt, net of current portion	0	0
Income taxes payable	3,270	3,470
Intercompany liabilities	0	0
Other long-term liabilities	18,741	20,952
Redeemable noncontrolling interests	0	0
IAC shareholders' equity	2,055,482	1,918,623
Noncontrolling interests	0	0
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	2,170,744	2,057,541
Non-Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	753,399	775,544	668,310	406,789
Marketable securities		0
Accounts receivable, net	189,761	142,803
Other current assets	119,753	96,762
Intercompany receivables	1,280,777	1,123,925
Property and equipment, net	156,146	142,594
Goodwill	2,089,579	1,512,042
Intangible assets, net	584,476	272,272
Investment in subsidiaries	0	0
Other non-current assets	356,853	165,482
TOTAL ASSETS	5,530,744	4,231,424
LIABILITIES AND SHAREHOLDERS' EQUITY
Current portion of long-term debt		0
Accounts payable	78,479	30,299
Other current liabilities	610,752	503,455
Long-term debt, net of current portion	1,253,998	1,176,493
Income taxes payable	30,009	30,274
Intercompany liabilities	0	0
Other long-term liabilities	53,877	51,867
Redeemable noncontrolling interests	40,981	32,827
IAC shareholders' equity	2,982,866	2,264,761
Noncontrolling interests	479,782	141,448
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	5,530,744	4,231,424
Eliminations
ASSETS
Cash and cash equivalents	0	0	$ 0	$ 0
Marketable securities		0
Accounts receivable, net	0	0
Other current assets	0	0
Intercompany receivables	(2,035,153)	(1,774,520)
Property and equipment, net	0	0
Goodwill	0	0
Intangible assets, net	0	0
Investment in subsidiaries	(5,038,348)	(4,183,384)
Other non-current assets	(191,429)	(115,473)
TOTAL ASSETS	(7,264,930)	(6,073,377)
LIABILITIES AND SHAREHOLDERS' EQUITY
Current portion of long-term debt		0
Accounts payable	0	0
Other current liabilities	0	0
Long-term debt, net of current portion	0	0
Income taxes payable	0	(216)
Intercompany liabilities	(2,035,153)	(1,774,520)
Other long-term liabilities	(191,429)	(115,257)
Redeemable noncontrolling interests	0	0
IAC shareholders' equity	(5,038,348)	(4,183,384)
Noncontrolling interests	0	0
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ (7,264,930)	$ (6,073,377)

GUARANTOR AND NON-GUARANTOR F64

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 828,434	$ 764,102	$ 2,356,654	$ 2,328,720
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	166,290	179,131	451,281	543,262
Selling and marketing expense	352,879	292,996	1,023,394	972,490
General and administrative expense	235,580	124,469	529,397	404,296
Product development expense	70,645	49,704	180,835	162,367
Depreciation	17,263	17,951	55,490	51,321
Amortization of intangibles	4,366	14,267	22,151	65,062
Goodwill impairment	0	0	0	275,367	$ 275,367
Total operating costs and expenses	847,023	678,518	2,262,548	2,474,165
Operating (loss) income	(18,589)	85,584	94,106	(145,445)
Equity in earnings (losses) of unconsolidated affiliates	0	0	0	0
Interest expense	(25,036)	(27,118)	(74,556)	(82,622)
Other (expense) income, net	(10,216)	11,700	(7,700)	20,405
(Loss) earnings before income taxes	(53,841)	70,166	11,850	(207,662)
Income tax benefit (provision)	279,480	(17,826)	322,809	77,394
Net earnings (loss)	225,639	52,340	334,659	(130,268)
Net earnings attributable to noncontrolling interests	(45,996)	(9,178)	(62,539)	(13,063)
Net earnings (loss) attributable to IAC shareholders	179,643	43,162	272,120	(143,331)
Comprehensive income (loss) attributable to IAC shareholders	216,868	37,885	338,730	(135,043)
IAC
Condensed Financial Statements, Captions [Line Items]
Revenue	0	0	0	0
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	0	219	159	811
Selling and marketing expense	312	546	1,250	2,306
General and administrative expense	32,060	22,375	93,974	66,208
Product development expense	593	1,009	2,098	4,127
Depreciation	406	422	1,290	1,274
Amortization of intangibles	0	0	0	0
Goodwill impairment				0
Total operating costs and expenses	33,371	24,571	98,771	74,726
Operating (loss) income	(33,371)	(24,571)	(98,771)	(74,726)
Equity in earnings (losses) of unconsolidated affiliates	203,808	71,471	346,643	(44,988)
Interest expense	(5,483)	(6,362)	(16,960)	(20,776)
Other (expense) income, net	(8,157)	(6,334)	(20,783)	(35,306)
(Loss) earnings before income taxes	156,797	34,204	210,129	(175,796)
Income tax benefit (provision)	22,846	8,958	61,991	32,465
Net earnings (loss)	179,643	43,162	272,120	(143,331)
Net earnings attributable to noncontrolling interests	0	0	0	0
Net earnings (loss) attributable to IAC shareholders	179,643	43,162	272,120	(143,331)
Comprehensive income (loss) attributable to IAC shareholders	216,868	37,885	338,730	(135,043)
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenue	185,386	206,107	536,789	710,915
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	41,741	63,730	104,581	201,326
Selling and marketing expense	84,416	87,051	258,634	323,681
General and administrative expense	15,676	20,243	46,777	65,491
Product development expense	13,145	16,453	42,324	55,334
Depreciation	3,822	6,051	15,799	17,144
Amortization of intangibles	350	6,100	10,102	35,183
Goodwill impairment				253,245
Total operating costs and expenses	159,150	199,628	478,217	951,404
Operating (loss) income	26,236	6,479	58,572	(240,489)
Equity in earnings (losses) of unconsolidated affiliates	4,229	(22,707)	8,170	(29,893)
Interest expense	0	0	0	0
Other (expense) income, net	8,311	4,837	21,207	11,251
(Loss) earnings before income taxes	38,776	(11,391)	87,949	(259,131)
Income tax benefit (provision)	(11,710)	(4,263)	(22,651)	81,742
Net earnings (loss)	27,066	(15,654)	65,298	(177,389)
Net earnings attributable to noncontrolling interests	0	0	0	0
Net earnings (loss) attributable to IAC shareholders	27,066	(15,654)	65,298	(177,389)
Comprehensive income (loss) attributable to IAC shareholders	26,789	(15,605)	67,276	(157,069)
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenue	643,175	558,154	1,820,373	1,618,178
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	124,676	115,226	346,975	341,346
Selling and marketing expense	268,181	205,620	763,640	646,777
General and administrative expense	187,814	81,745	388,590	272,475
Product development expense	56,907	32,242	136,413	102,906
Depreciation	13,035	11,478	38,401	32,903
Amortization of intangibles	4,016	8,167	12,049	29,879
Goodwill impairment				22,122
Total operating costs and expenses	654,629	454,478	1,686,068	1,448,408
Operating (loss) income	(11,454)	103,676	134,305	169,770
Equity in earnings (losses) of unconsolidated affiliates	0	0	0	0
Interest expense	(19,553)	(20,756)	(57,596)	(61,846)
Other (expense) income, net	(10,370)	13,197	(8,124)	44,460
(Loss) earnings before income taxes	(41,377)	96,117	68,585	152,384
Income tax benefit (provision)	268,344	(22,521)	283,469	(36,813)
Net earnings (loss)	226,967	73,596	352,054	115,571
Net earnings attributable to noncontrolling interests	(45,996)	(9,178)	(62,539)	(13,063)
Net earnings (loss) attributable to IAC shareholders	180,971	64,418	289,515	102,508
Comprehensive income (loss) attributable to IAC shareholders	224,929	59,542	373,635	108,007
Eliminations
Condensed Financial Statements, Captions [Line Items]
Revenue	(127)	(159)	(508)	(373)
Operating costs and expenses:
Cost of revenue (exclusive of depreciation shown separately below)	(127)	(44)	(434)	(221)
Selling and marketing expense	(30)	(221)	(130)	(274)
General and administrative expense	30	106	56	122
Product development expense	0	0	0	0
Depreciation	0	0	0	0
Amortization of intangibles	0	0	0	0
Goodwill impairment				0
Total operating costs and expenses	(127)	(159)	(508)	(373)
Operating (loss) income	0	0	0	0
Equity in earnings (losses) of unconsolidated affiliates	(208,037)	(48,764)	(354,813)	74,881
Interest expense	0	0	0	0
Other (expense) income, net	0	0	0	0
(Loss) earnings before income taxes	(208,037)	(48,764)	(354,813)	74,881
Income tax benefit (provision)	0	0	0	0
Net earnings (loss)	(208,037)	(48,764)	(354,813)	74,881
Net earnings attributable to noncontrolling interests	0	0	0	0
Net earnings (loss) attributable to IAC shareholders	(208,037)	(48,764)	(354,813)	74,881
Comprehensive income (loss) attributable to IAC shareholders	$ (251,718)	$ (43,937)	$ (440,911)	$ 49,062

GUARANTOR AND NON-GUARANTOR F65

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Statement of Cash Flows (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	$ 297,597	$ 194,259
Cash flows from investing activities:
Acquisitions, net of cash acquired	(69,113)	(2,524)
Capital expenditures	(56,519)	(62,739)
Investments in time deposits	0	(87,500)
Proceeds from maturities of time deposits	0	87,500
Proceeds from maturities and sales of marketable debt securities	114,350	79,210
Purchases of marketable debt securities	(24,909)	(229,246)
Purchases of investments	(9,105)	(7,211)
Net proceeds from the sale of businesses and investments	125,220	110,536
Intercompany	0	0
Other, net	1,319	5,562
Net cash provided by (used in) investing activities	81,243	(106,412)
Cash flows from financing activities:
Purchase of IAC treasury stock	(56,424)	(247,256)
Proceeds from Match Group 6.375% Senior Notes offering	0	400,000
Proceeds from Match Group Term Loan	75,000	0
Principal payment on Match Group Term Loan	0	(410,000)
Debt issuance costs	(2,637)	(5,048)
Repurchases of IAC Senior Notes	(31,590)	(126,271)
Proceeds from the exercise of IAC stock options	69,065	19,536
Withholding taxes paid on behalf of IAC net settled stock-based awards	(57,180)	(26,684)
Proceeds from the exercise of Match Group stock options	57,705	30,246
Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards	(501,437)	(29,779)
Purchase of noncontrolling interests	(13,011)	(2,529)
Acquisition-related contingent consideration payments	(27,289)	(2,180)
Funds returned from escrow for MyHammer tender offer	10,604	0
Decrease in restricted cash related to bond redemptions	20,141	20,000
Intercompany	0	0
Other, net	(5,002)	(766)
Net cash used in financing activities	(462,055)	(380,731)
Total cash used	(83,215)	(292,884)
Effect of exchange rate changes on cash and cash equivalents	9,345	1,221
Net decrease in cash and cash equivalents	(73,870)	(291,663)
Cash and cash equivalents at beginning of period	1,329,187	1,481,447
Cash and cash equivalents at end of period	1,255,317	1,189,784
IAC
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	(35,286)	(60,394)
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	0
Capital expenditures	(337)	(343)
Investments in time deposits		0
Proceeds from maturities of time deposits		0
Proceeds from maturities and sales of marketable debt securities	114,350	79,210
Purchases of marketable debt securities	(24,909)	(229,246)
Purchases of investments	0	0
Net proceeds from the sale of businesses and investments	911	15,401
Intercompany	(108,258)	(58,998)
Other, net	0	0
Net cash provided by (used in) investing activities	(18,243)	(193,976)
Cash flows from financing activities:
Purchase of IAC treasury stock	(56,424)	(247,256)
Proceeds from Match Group 6.375% Senior Notes offering		0
Proceeds from Match Group Term Loan	0
Principal payment on Match Group Term Loan		0
Debt issuance costs	0	0
Repurchases of IAC Senior Notes	(31,590)	(126,271)
Proceeds from the exercise of IAC stock options	69,065	19,536
Withholding taxes paid on behalf of IAC net settled stock-based awards	(57,180)	(26,684)
Proceeds from the exercise of Match Group stock options	0	0
Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards	0	0
Purchase of noncontrolling interests	0	(1,400)
Acquisition-related contingent consideration payments	0	0
Funds returned from escrow for MyHammer tender offer	0
Decrease in restricted cash related to bond redemptions	20,141	20,000
Intercompany	57,460	63,261
Other, net	251	0
Net cash used in financing activities	1,723	(298,814)
Total cash used	(51,806)	(553,184)
Effect of exchange rate changes on cash and cash equivalents	81	0
Net decrease in cash and cash equivalents	(51,725)	(553,184)
Cash and cash equivalents at beginning of period	553,643	1,074,658
Cash and cash equivalents at end of period	501,918	521,474
Guarantor Subsidiaries
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	76,616	66,421
Cash flows from investing activities:
Acquisitions, net of cash acquired	(2,200)	0
Capital expenditures	(17,263)	(4,747)
Investments in time deposits		0
Proceeds from maturities of time deposits		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 proceeds from the sale of businesses and investments	0	1,779
Intercompany	0	0
Other, net	307	158
Net cash provided by (used in) investing activities	(19,156)	(2,810)
Cash flows from financing activities:
Purchase of IAC treasury stock	0	0
Proceeds from Match Group 6.375% Senior Notes offering		0
Proceeds from Match Group Term Loan	0
Principal payment on Match Group Term Loan		0
Debt issuance costs	0	0
Repurchases of IAC Senior Notes	0	0
Proceeds from the exercise of IAC stock options	0	0
Withholding taxes paid on behalf of IAC net settled stock-based awards	0	0
Proceeds from the exercise of Match Group stock options	0	0
Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards	0	0
Purchase of noncontrolling interests	0	0
Acquisition-related contingent consideration payments	0	(351)
Funds returned from escrow for MyHammer tender offer	0
Decrease in restricted cash related to bond redemptions	0	0
Intercompany	(57,460)	(63,260)
Other, net	0	0
Net cash used in financing activities	(57,460)	(63,611)
Total cash used	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0
Net decrease in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Non-Guarantor Subsidiaries
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	256,267	188,232
Cash flows from investing activities:
Acquisitions, net of cash acquired	(66,913)	(2,524)
Capital expenditures	(38,919)	(57,649)
Investments in time deposits		(87,500)
Proceeds from maturities of time deposits		87,500
Proceeds from maturities and sales of marketable debt securities	0	0
Purchases of marketable debt securities	0	0
Purchases of investments	(9,105)	(7,211)
Net proceeds from the sale of businesses and investments	124,309	93,356
Intercompany	0	0
Other, net	1,012	5,404
Net cash provided by (used in) investing activities	10,384	31,376
Cash flows from financing activities:
Purchase of IAC treasury stock	0	0
Proceeds from Match Group 6.375% Senior Notes offering		400,000
Proceeds from Match Group Term Loan	75,000
Principal payment on Match Group Term Loan		(410,000)
Debt issuance costs	(2,637)	(5,048)
Repurchases of IAC Senior Notes	0	0
Proceeds from the exercise of IAC stock options	0	0
Withholding taxes paid on behalf of IAC net settled stock-based awards	0	0
Proceeds from the exercise of Match Group stock options	57,705	30,246
Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards	(501,437)	(29,779)
Purchase of noncontrolling interests	(13,011)	(1,129)
Acquisition-related contingent consideration payments	(27,289)	(1,829)
Funds returned from escrow for MyHammer tender offer	10,604
Decrease in restricted cash related to bond redemptions		0
Intercompany	108,258	58,997
Other, net	(5,253)	(766)
Net cash used in financing activities	(298,060)	40,692
Total cash used	(31,409)	260,300
Effect of exchange rate changes on cash and cash equivalents	9,264	1,221
Net decrease in cash and cash equivalents	(22,145)	261,521
Cash and cash equivalents at beginning of period	775,544	406,789
Cash and cash equivalents at end of period	753,399	668,310
Eliminations
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	0	0
Cash flows from investing activities:
Acquisitions, net of cash acquired	0	0
Capital expenditures	0	0
Investments in time deposits		0
Proceeds from maturities of time deposits		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 proceeds from the sale of businesses and investments	0	0
Intercompany	108,258	58,998
Other, net	0	0
Net cash provided by (used in) investing activities	108,258	58,998
Cash flows from financing activities:
Purchase of IAC treasury stock	0	0
Proceeds from Match Group 6.375% Senior Notes offering		0
Proceeds from Match Group Term Loan	0
Principal payment on Match Group Term Loan		0
Debt issuance costs	0	0
Repurchases of IAC Senior Notes	0	0
Proceeds from the exercise of IAC stock options	0	0
Withholding taxes paid on behalf of IAC net settled stock-based awards	0	0
Proceeds from the exercise of Match Group stock options	0	0
Cash payments to purchase fully vested equity awards and pay withholding taxes on behalf of Match Group employees on net settled stock-based awards	0	0
Purchase of noncontrolling interests	0	0
Acquisition-related contingent consideration payments	0	0
Funds returned from escrow for MyHammer tender offer	0
Decrease in restricted cash related to bond redemptions	0	0
Intercompany	(108,258)	(58,998)
Other, net	0	0
Net cash used in financing activities	(108,258)	(58,998)
Total cash used	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0
Net decrease in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$ 0	$ 0

SUBSEQUENT EVENTS - Narrative (

SUBSEQUENT EVENTS - Narrative (Details) $ / shares in Units, shares in Millions	Nov. 01, 2017USD ($)	Oct. 23, 2017USD ($)	Oct. 02, 2017USD ($)$ / sharesshares	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Subsequent Event [Line Items]
Repurchase and redemption of Senior Notes				$ 31,590,000	$ 126,271,000
Subsequent Event
Subsequent Event [Line Items]
Payment of net premium on exchangeable note hedge and warrants			$ 50,700,000
Payment of accrued interest			$ 8,800,000
Strike price of call options purchased (in dollars per share) | $ / shares			$ 152.18
Number of shares that would be issuable upon conversion of notes | shares			3.4
Number of securities called by warrants | shares			3.4
Exercise price of warrants | $ / shares			$ 229.70
Subsequent Event | Cost-method Investment | Zhenai Inc
Subsequent Event [Line Items]
Proceeds from sale of cost method investments		$ 60,200,000
0.875% Exchangeable Senior Notes due October 1, 2022 | Senior Notes | Subsequent Event
Subsequent Event [Line Items]
Proceeds from issuance of senior notes			$ 500,500,000
Exchange rate for notes (in shares per $1000)			6.5713
Principal amount per note			$ 1,000
Initial exchange price (in dollars per share) | $ / shares			$ 152.18
0.875% Exchangeable Senior Notes due October 1, 2022 | Senior Notes | Subsidiary | Subsequent Event
Subsequent Event [Line Items]
Debt instrument, face amount			$ 517,500,000
Stated interest rate (as a percent)			0.875%
4.875% Senior Notes due November 30, 2018 | Senior Notes
Subsequent Event [Line Items]
Stated interest rate (as a percent)				4.875%	4.875%
4.875% Senior Notes due November 30, 2018 | Senior Notes | Subsequent Event
Subsequent Event [Line Items]
Stated interest rate (as a percent)			4.875%
Repurchase and redemption of Senior Notes			$ 361,900,000
ANGI Homeservices Term Loan | Term Loan | Subsequent Event
Subsequent Event [Line Items]
Debt instrument, face amount	$ 275,000,000
Debt instrument, term	5 years
Term loan quarterly amortization rate, years 1-3 (percent)	1.25%
Term loan quarterly amortization rate, year 4 (percent)	2.50%
Term loan quarterly amortization rate, after year 5 (percent)	3.75%
ANGI Homeservices Term Loan | Term Loan | Subsequent Event | LIBOR
Subsequent Event [Line Items]
Basis spread on variable rate (as a percent)	2.00%