Yelp (YELP) 10-Q 1 May 15 2015 Q1 Quarterly report Financial data

DOCUMENT_AND_ENTITY_INFORMATIO

DOCUMENT AND ENTITY INFORMATION	3 Months Ended
	Mar. 31, 2015	Apr. 24, 2015
Document Type	10-Q
Document Period End Date	31-Mar-15
Amendment Flag	FALSE
Entity Registrant Name	YELP INC
Entity Central Index Key	1345016
Trading Symbol	YELP
Current Fiscal Year End Date	-19
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Entity Filer Category	Large Accelerated Filer
Class A common stock [Member]
Entity Common Stock, Shares Outstanding		65,213,955
Class B common stock [Member]
Entity Common Stock, Shares Outstanding		9,571,608

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$172,629	$247,312
Short-term marketable securities	158,603	118,498
Accounts receivable (net of allowance for doubtful accounts of $2,323 and $1,627 at March 31, 2015 and December 31, 2014, respectively)	38,969	35,593
Prepaid expenses and other current assets	22,706	19,355
Total current assets	392,907	420,758
Long-term marketable securities	16,495	38,612
Property, equipment and software, net	68,594	62,761
Goodwill	172,160	67,307
Intangibles, net	44,187	5,786
Restricted cash	17,899	17,943
Other assets	3,644	16,483
Total Assets	715,886	629,650
Current liabilities:
Accounts payable	1,836	1,398
Accrued liabilities	41,888	29,581
Deferred revenue	3,657	2,994
Total current liabilities	47,381	33,973
Long-term liabilities	11,849	7,527
Total liabilities	59,230	41,500
Commitments and contingencies (Note 10)
Stockholders' Equity
Common stock, $0.000001 par value - 500,000,000 shares authorized; 74,651,334 and 72,920,582 shares issued and outstanding at March 31, 2015 and December 31, 2014, respectively
Additional paid-in capital	705,397	627,742
Accumulated other comprehensive income	-13,474	-5,609
Accumulated deficit	-35,267	-33,983
Total stockholders' equity	656,656	588,150
Total liabilities and stockholders' equity	$715,886	$629,650

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
CONDENSED CONSOLIDATED BALANCE SHEETS [Abstract]
Allowance for doubtful accounts	$2,323	$1,627
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	74,651,334	72,920,582
Common stock, shares outstanding	74,651,334	72,920,582

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net revenue	$118,508	$76,407
Costs and expenses:
Cost of revenue (exclusive of depreciation and amortization shown separately below)	8,699	5,077
Sales and marketing	63,266	45,121
Product development	23,960	13,982
General and administrative	19,937	13,170
Depreciation and amortization	6,895	3,661
Total costs and expenses	122,757	81,011
Loss from operations	-4,249	-4,604
Other income (expense), net	562	-2
Loss before income taxes	-3,687	-4,606
Benefit from income taxes	2,403	1,971
Net loss attributable to common stockholders (Class A and B)	($1,284)	($2,635)
Net loss per share attributable to common stockholders (Class A and B)
Basic	($0.02)	($0.04)
Diluted	($0.02)	($0.04)
Weighted-average shares used to compute net loss per share attributable to common stockholders (Class A and B)
Basic	73,684	71,171
Diluted	73,684	71,171

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS [Abstract]
Net loss	($1,284)	($2,635)
Other comprehensive income (loss):
Foreign currency translation adjustments	-7,864	-84
Other comprehensive income (loss)	-7,864	-84
Comprehensive loss	($9,148)	($2,719)

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
OPERATING ACTIVITIES:
Net loss	($1,284)	($2,635)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	6,895	3,661
Provision for doubtful accounts and sales returns	3,434	1,186
Stock-based compensation	13,671	9,456
Loss on disposal of assets and website development costs	52
Premium amortization, net, on securities held-to-maturity	-117
Excess tax benefit from stock-based award activity	-815	-39
Changes in operating assets and liabilities:
Accounts receivable	-2,850	-1,249
Prepaid expenses and other assets	-6,045	-5,928
Accounts payable and accrued expenses	12,011	5,309
Deferred revenue	683	-438
Net cash provided by operating activities	25,635	9,323
INVESTING ACTIVITIES:
Acquisition, net of cash received	-71,546
Purchases of property, equipment and software	-10,881	-4,246
Capitalized website and software development costs	-3,196	-1,592
Proceeds from sale of property and equipment	97
Purchases of intangible assets	-314
Maturities of investment securities, held-to-maturity	18,250
Purchases of investment securities, held-to-maturity	-36,120
Changes in restricted cash	-5	-397
Net cash used in investing activities	-103,715	-6,235
FINANCING ACTIVITIES:
Proceeds from exercise of employee stock options	3,398	6,735
Excess tax benefit from stock-based award activity	815	39
Repurchase of common stock	-168	-361
Net cash provided by financing activities	4,045	6,413
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	-648	55
CHANGE IN CASH AND CASH EQUIVALENTS	-74,683	9,556
CASH AND CASH EQUIVALENTS-Beginning of period	247,312	389,764
CASH AND CASH EQUIVALENTS-End of period	172,629	399,320
SUPPLEMENTAL DISCLOSURES OF OTHER CASH FLOW INFORMATION:
Cash paid for income taxes, net of refunds	422	115
SUPPLEMENTAL DISCLOSURES OF NONCASH INVESTING AND FINANCING ACTIVITIES:
Purchases of property and equipment recorded in accounts payable and accruals	3,544	1,880
Capitalized website and software development costs recorded in accounts payable and accruals	15	67
Acquisition consideration included in accruals	1,876
Goodwill measurement period adjustment for working capital	$51

DESCRIPTION_OF_BUSINESS_AND_BA

DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2015
DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION [Abstract]
DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION	1. DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION
	Yelp Inc. was incorporated in Delaware on September 3, 2004. Except where specifically noted or the context otherwise requires, the use of terms such as the “Company” and “Yelp” in these Notes to Condensed Consolidated Financial Statements refers to Yelp Inc. and its subsidiaries.
	Yelp connects people with great local businesses by bringing “word of mouth” online and providing a platform for businesses and consumers to engage and transact. Yelp's platform is transforming the way people discover local businesses; every day, millions of consumers visit its website or use its mobile app to find local businesses to meet their everyday needs. Businesses of all sizes use the Yelp platform to engage with consumers at the critical moment when they are deciding where to spend their money.
	Basis of Presentation
	The accompanying interim condensed consolidated financial statements are unaudited. These unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these unaudited interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements contained in the Company's Annual Report on Form 10-K filed with the SEC on February 27, 2015 (the “Annual Report”). The unaudited condensed consolidated balance sheet as of December 31, 2014 included herein was derived from the audited consolidated financial statements as of that date, but does not include all disclosures required by GAAP, including certain notes to the financial statements.
	The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, include all adjustments of a normal recurring nature necessary for the fair presentation of the interim periods presented.
	Significant Accounting Policies
	There have been no material changes to the Company's significant accounting policies from those described in the Annual Report.
	Recent Accounting Pronouncements Not Yet Effective
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update 2014-09, “Revenue from Contracts with Customers” (“ASU 2014-09”), which amended the existing accounting standards for revenue recognition. ASU 2014-09 establishes principles for recognizing revenue upon the transfer of promised goods or services to customers, in an amount that reflects the consideration expected to be received in exchange for those goods or services. The updated standard will replace most existing GAAP revenue recognition guidance when it becomes effective, and permits the use of either the retrospective or cumulative effect transition method. Early adoption of this accounting standard is not permitted. ASU 2014-09 will become effective for the Company in the first quarter of the year ending December 31, 2017. The Company has not yet selected a transition method and is currently evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures.
	In August 2014, FASB issued Accounting Standards Update 2014-15, “Presentation of Financial Statements — Going Concern (Subtopic 205-40).” The new guidance addresses management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern and to provide related footnote disclosures. Management's evaluation should be based on relevant conditions and events that are known and reasonably knowable at the date that the financial statements are issued. The standard will be effective for the first interim period within annual reporting periods beginning after December 15, 2016. Early adoption is permitted. The Company does not expect to early adopt this guidance and does not believe that the adoption of this guidance will have a material impact on its consolidated financial statements.
	Principles of Consolidation
	These unaudited interim condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
	Use of Estimates
	The preparation of the Company's unaudited interim condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the reporting period. These estimates are based on information available as of the date of the unaudited interim condensed consolidated financial statements; therefore, actual results could differ from management's estimates.

FAIR_VALUE_OF_FINANCIAL_INSTRU

FAIR VALUE OF FINANCIAL INSTRUMENTS	3 Months Ended
	Mar. 31, 2015
FAIR VALUE OF FINANCIAL INSTRUMENTS [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	2. FAIR VALUE OF FINANCIAL INSTRUMENTS
	The Company's investments in money market accounts are recorded at fair value in the condensed consolidated financial statements. All other financial instruments are classified as held-to-maturity investments and, accordingly, are recorded at amortized cost; however, the Company is required to determine the fair value of these investments on a recurring basis to identify any potential impairment. The accounting guidance for fair value measurements prioritizes the inputs used in measuring fair value in the following hierarchy:
	Level 1—Observable inputs, such as quoted prices in active markets,
	Level 2—Inputs other than quoted prices in active markets that are observable either directly or indirectly, or
	Level 3—Unobservable inputs for which there is little or no market data, which requires the Company to develop its own assumptions.
	This hierarchy requires the Company to use observable market data, when available, to minimize the use of unobservable inputs when determining fair value. The Company's money market funds and U.S. government bonds are classified within Level 1 of the fair value hierarchy because they are valued using quoted prices in active markets. The Company's commercial paper, corporate bonds and agency bonds are classified within Level 2 of the fair value hierarchy because they have been valued using inputs other than quoted prices in active markets that are observable directly or indirectly.
	The Company classifies the contingent consideration liability, which is related to the acquisition of Restaurant Kritik, within Level 3, because it was estimated using a discounted cash flow technique with significant inputs that are not observable in the market. The significant inputs not observable in the market in the Level 3 measurement included the Company's probability assessments of completion, appropriately discounted considering the uncertainties associated with the obligation, and were calculated in accordance with the terms of the asset purchase agreement. Refer to Note 4 regarding the effects of the acquisition on the Company's consolidated financial statements.
	The following table represents the Company's financial instruments measured at fair value as of March 31, 2015 and December 31, 2014 (in thousands):
		31-Mar-15								31-Dec-14
		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
	Cash Equivalents:
	Money market funds	$	115,506		—		—		115,506	$	208,593	$	—	$	—	$	208,593
	Marketable Securities:
	U.S. government bonds		5,005		—		—		5,005		5,005		—		—		5,005
	Commercial paper		—		33,979				33,979		—		31,965		—		31,965
	Corporate bonds		—		29,267				29,267		—		29,486		—		29,486
	Agency bonds		—		106,829				106,829		—		90,575		—		90,575
	Total cash equivalents and marketable securities	$	120,511	$	170,075	$		$	290,586	$	213,598	$	152,026	$	—	$	365,624
	Current liabilities:
	Contingent consideration liability	$	—	$	—	$	785	$	785	$	—	$	—	$	835	$	835

MARKETABLE_SECURITIES

MARKETABLE SECURITIES	3 Months Ended
	Mar. 31, 2015
MARKETABLE SECURITIES [Abstract]
MARKETABLE SECURITIES	3. MARKETABLE SECURITIES
	The amortized cost, gross unrealized gains and losses, and fair value of securities held-to-maturity, all of which mature within two years, as of March 31, 2015 were as follows (in thousands):
		As of March 31, 2015
				Gross			Gross
				Unrealized			Unrealized
		Amortized Cost		Gains			Losses				Fair Value
	Short-term marketable securities:
	Commercial paper	$	33,979	$	—		$	—			$	33,979
	Corporate bonds		29,280		7			(20	)			29,267
	Agency bonds		90,339		8			(10	)			90,337
	U.S. government bonds		5,005		—			—				5,005
		$	158,603	$	15		$	(30	)		$	158,588
	Long-term marketable securities:
	Agency bonds		16,495		—			(3	)			16,492
		$	16,495	$	—		$	(3	)		$	16,492
	Total marketable securities	$	175,098	$	15		$	(33	)		$	175,080
	The following table presents gross unrealized losses and fair values for those securities that were in an unrealized loss position as of March 31, 2015, aggregated by investment category and the length of time that the individual securities have been in a continuous loss position (in thousands):
		As of March 31, 2015
		Less Than 12 Months							12 Months or Greater				Total
		Fair Value		Unrealized Loss					Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
	Corporate bonds	$	14,127	$	(20	)			$	—	$	—	$	14,127	$	(20	)
	Agency bonds		67,238		(13	)				—		—		67,238		(13	)
	Total	$	81,365	$	(33	)			$	—	$	—	$	81,365	$	-33
	The Company periodically reviews its investment portfolio for other-than-temporary impairment. The Company considers such factors as the duration, severity and reason for the decline in value, and the potential recovery period. The Company also considers whether it is more likely than not that it will be required to sell the securities before the recovery of their amortized cost basis, and whether the amortized cost basis cannot be recovered as a result of credit losses. During the three months ended March 31, 2015, the Company did not recognize any other-than-temporary impairment loss. The Company had no investments in marketable securities outside of money market funds prior to April 1, 2014.

ACQUISITIONS

ACQUISITIONS	3 Months Ended
	Mar. 31, 2015
ACQUISITIONS [Abstract]
ACQUISITIONS	4. ACQUISITIONS
	2015 Acquisition
	On February 9, 2015, the Company acquired Eat24Hours.com, Inc. (“Eat24”). In connection with the acquisition, all of the outstanding capital stock of Eat24 was converted into the right to receive an aggregate of approximately $75.0 million in cash, less certain transaction expenses, and 1,402,844 shares of Yelp Class A common stock with an aggregate fair value of approximately $59.2 million, as determined on the basis of the closing market price of the Company's Class A common stock on the acquisition date. Of the total consideration paid in connection with the acquisition, $16.5 million in cash and 308,626 shares were initially held in escrow to secure indemnification obligations. The key factor underlying the acquisition was to obtain an online food ordering solution to drive daily engagement in its key restaurant vertical.
	The acquisition was accounted for as a business combination in accordance with Accounting Standards Codification Topic 805, “Business Combinations” (“ASC 805”), with the results of Eat24's operations included in the Company's consolidated financial statements from February 9, 2015. The Company's allocation of the purchase price is preliminary as the amounts related to contingent consideration, identifiable intangible assets, the effects of income taxes resulting from the transaction, and the effects of any net working capital adjustments are still being finalized. Any material measurement period adjustments will be recorded retroactively to the acquisition date.  The purchase price allocation, subject to finalization during the measurement period, is as follows (in thousands):
		9-Feb-15
	Fair value of purchase consideration:
	Cash:
	Distributed to Eat24 stockholders	$	56,624
	Held in escrow account		16,500
	Payable on behalf of Eat24 stockholders		1,876
	Total cash		75,000
	Class A common stock:
	Distributed to Eat24 stockholders		46,143
	Held in escrow account		13,015
	Total purchase consideration	$	134,158
	Fair value of net assets acquired:
	Cash and cash equivalents	$	1,578
	Intangibles		39,600
	Goodwill		110,927
	Other assets		6,031
	Total assets acquired		158,136
	Deferred tax liability		(15,207	)
	Other liabilities		(8,771	)
	Total liabilities assumed		(23,978	)
	Net assets acquired	$	134,158
	Estimated useful lives and the amount assigned to each class of intangible assets acquired are as follows:
	Intangible Type		Amount Assigned		Useful Life
	Restaurant relationships		17,400		12.0 years
	Developed technology		7,400		5.0 years
	User relationships		12,000		7.0 years
	Trade name		2,800		4.0 years
	Weighted average				8.6 years
	The intangible assets are being amortized on a straight-line basis, which reflects the pattern in which the economic benefits of the intangible assets are being utilized. The goodwill results from the Company's opportunity to drive daily engagement in its restaurant vertical and potentially expand Eat24's offering to the approximately 1 million U.S. restaurants listed on the Company's platform. None of the goodwill is deductible for tax purposes.
	For the quarter ended March 31, 2015, the Company recorded acquisition-related transaction costs of approximately $0.2 million, which were included in general and administrative expense in the accompanying consolidated statement of operations.
	The unaudited pro forma financial information in the table below summarizes the combined results of operations for the Company and Eat24, as though the companies had been combined as of January 1, 2014, and includes the accounting effects resulting from the acquisition, including transaction, integration costs, amortization charges from acquired intangible assets, and changes in depreciation due to differing asset values and depreciation lives. The unaudited pro forma financial information, as presented below, is for informational purposes only and is not necessarily indicative of the results of operations that would have been achieved if the acquisition had taken place as of January 1, 2014 (in thousands, except per share data):
		Pro Forma for the Three Months Ended March 31,
		2015				2014
	Revenue	$	121,753			$	81,860
	Net loss	$	(2,402	)		$	(3,518	)
	Basic and diluted net loss per share attributable to common stockholders	$	(0.03	)		$	(0.05	)
	Since the acquisition date, $5.3 million of revenue and $0.4 million of net loss attributable to Eat24 are included in the consolidated statement of operations for the three months ended March 31, 2015.
	2014 Acquisitions
	In October 2014, the Company, through its wholly-owned subsidiary, Yelp Ireland Ltd., completed the acquisition of all of the outstanding equity interests in Cityvox SAS. Also in October 2014, the Company, through its wholly-owned subsidiaries Yelp Ireland Ltd. and Qype GmbH, acquired the assets comprising the business conducted under the name Restaurant Kritik from Kabukiman Ltd. The aggregate purchase price of these businesses was $15.3 million, net of $0.1 million cash acquired; the purchase price did not include stock in either transaction. Each of these acquisitions has been accounted for as a business combination in accordance with ASC 805, under the acquisition method. Accordingly, the aggregate purchase price is allocated to the tangible and intangible assets acquired and the liabilities assumed based on their respective fair values on the acquisition dates, and is subject to adjustment based on purchase price adjustment provisions contained in the acquisition agreements. The results of operations of the acquired companies have been included in the Company's consolidated financial statements from the respective acquisition dates. Net revenues, earnings since the acquisition and pro forma results of operations for these acquisitions have not been presented because they are not material to the consolidated results of operations, either individually or in aggregate. During the quarter ended December 31, 2014, the Company recorded acquisition-related transaction costs of $0.6 million, which were included in general and administrative expense.
	Under the Restaurant Kritik asset purchase agreement, the Company agreed to pay an additional $0.9 million in consideration if the migration of Restaurant Kritik's content to Yelp is completed within one year of the acquisition date. The estimated fair value of the contingent consideration was approximately $0.8 million as of the acquisition date and $0.8 million as of March 31, 2015, and is included in current liabilities on the Company's consolidated balance sheet.
	The following table presents the aggregate purchase price allocations of these individually immaterial acquisitions recorded in the Company's condensed consolidated balance sheets as of their acquisition dates (in thousands):
	Net tangible assets	$	(277	)
	Goodwill		13,995
	Intangible assets		1,546
	Total purchase price (excluding contingent consideration)		15,264
	Contingent consideration		826
	Total purchase price	$	16,090
	Estimated useful lives as of the acquisition dates of the intangible assets acquired are as follows:
	Intangible Type	Useful Life
	Content	5 years
	Developed technology	0.5 years
	Trade name	2 years
	Weighted average	4.3 years
	The intangible assets are being amortized on a straight-line basis, which reflects the pattern in which the economic benefits of the intangible assets are being utilized. The goodwill represents the excess value over both tangible and intangible assets acquired. The goodwill in these transactions is primarily attributable to traffic and the opportunity for expansion. None of the goodwill is deductible for tax purposes.
	2012 Acquisition
	On October 23, 2012, the Company, through Yelp Ireland Ltd., completed the acquisition of all the outstanding equity interests of Qype GmbH and its subsidiaries (collectively, “Qype”) for approximately $24.3 million in cash and Yelp Class A common stock with an approximate fair value of $23.3 million. Of the total consideration paid in connection with the acquisition, $10.3 million was held in the form of cash in escrow to secure indemnification obligations. In March 2015, approximately $0.7 million was released to the Company from the escrow fund relating to this acquisition, and is included in other income (expense), net. The remaining funds were distributed to the former Qype shareholders; accordingly, the balance remaining in the escrow fund was zero as of March 31, 2015.

CASH_AND_CASH_EQUIVALENTS

CASH AND CASH EQUIVALENTS	3 Months Ended
	Mar. 31, 2015
CASH AND CASH EQUIVALENTS [Abstract]
CASH AND CASH EQUIVALENTS	5. CASH AND CASH EQUIVALENTS
	Cash and cash equivalents as of March 31, 2015 and December 31, 2014 consist of the following (in thousands):
		March 31,		December 31,
		2015		2014
	Cash and cash equivalents
	Cash	$	57,123	$	38,719
	Money market funds		115,506		208,593
	Total cash and cash equivalents	$	172,629	$	247,312
	The lease agreements for certain of the Company's offices require the Company to maintain letters of credit issued to the landlords of each facility. Each letter of credit is subject to renewal annually until the applicable lease expires and is collateralized by restricted cash. As of March 31, 2015 and December 31, 2014, the Company had letters of credit totaling $17.9 million related to such leases.

PROPERTY_EQUIPMENT_AND_SOFTWAR

PROPERTY, EQUIPMENT AND SOFTWARE, NET	3 Months Ended
	Mar. 31, 2015
PROPERTY, EQUIPMENT AND SOFTWARE, NET [Abstract]
PROPERTY, EQUIPMENT AND SOFTWARE, NET	6. PROPERTY, EQUIPMENT AND SOFTWARE, NET
	Property, equipment and software, net as of March 31, 2015 and December 31, 2014 consist of the following (in thousands):
		March 31,			December 31,
		2015			2014
	Computer equipment	$	20,755		$	19,111
	Software		820			802
	Capitalized website and internal-use software development costs		31,372			27,602
	Furniture and fixtures		8,569			6,621
	Leasehold improvements		39,545			36,991
	Telecommunication		2,623			2,610
	Total		103,684			93,737
	Less accumulated depreciation		(35,090	)		(30,976	)
	Property, equipment and software, net	$	68,594		$	62,761
	Depreciation expense for the three months ended March 31, 2015 and 2014 was approximately $5.6 million and $2.8 million, respectively.

GOODWILL_AND_INTANGIBLE_ASSETS

GOODWILL AND INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2015
GOODWILL AND INTANGIBLE ASSETS [Abstract]
GOODWILL AND INTANGIBLE ASSETS	7. GOODWILL AND INTANGIBLE ASSETS
	The Company's goodwill is the result of its acquisitions of other businesses, and represents the excess of purchase consideration over the fair value of assets and liabilities acquired.
	The changes in the carrying amount of goodwill during the three months ended March 31, 2015 were as follows (in thousands):
	Balance as of December 31, 2014	$	67,307
	Goodwill measurement period adjustment		51
	Goodwill acquired		110,927
	Effect of currency translation		(6,125	)
	Balance as of March 31, 2015	$	172,160
	Intangible assets at March 31, 2015 and December 31, 2014 consist of the following (dollars in thousands):
											Weighted
				Gross					Net		Average
				Carrying		Accumulated			Carrying		Remaining
				Amount		Amortization			Amount		Life
	March 31, 2015:
	Restaurant and user relationships			$	29,400	$	(401	)	$	28,999		9.7 years
	Developed and acquired technology				9,291		(1,131	)		8,160		4.8 years
	Content				3,909		(1,470	)		2,439		3.4 years
	Data licenses and domains				2,291		(497	)		1,794		3.6 years
	Trade name and other				3,347		(552	)		2,795		3.7 years
	Total			$	48,238	$	(4,051	)	$	44,187
												Weighted
				Gross					Net		Average
				Carrying		Accumulated			Carrying		Remaining
				Amount		Amortization			Amount		Life
	December 31, 2014:
	Developed and acquired technology			$	1,963		(861	)	$	1,102		4.2 years
	Advertiser relationships				1,853		(1,853	)		—		0.0 years
	Content				4,299	$	(1,393	)		2,906		3.6 years
	Data licenses and domains				1,977		(326	)		1,651		4.5 years
	Trade name and other				596		(469	)		127		1.4 years
	Total			$	10,688	$	(4,902	)	$	5,786
	Amortization expense for the three months ended March 31, 2015 and 2014 was $1.2 million and $0.6 million, respectively.
	As of March 31, 2015, the estimated future amortization of purchased intangible assets for (i) the remaining nine months of 2015, (ii) each of the succeeding four years and (iii) the succeeding fifth year and thereafter are as follows (in thousands):
	Year Ending December 31,		Amount
	2015 (from April 1, 2015)		$	5,138
	2016			6,781
	2017			6,638
	2018			6,176
	2019			5,304
	2020 and thereafter			14,150
	Total amortization		$	44,187

ACCRUED_LIABILITIES

ACCRUED LIABILITIES	3 Months Ended
	Mar. 31, 2015
ACCRUED LIABILITIES [Abstract]
ACCRUED LIABILITIES	8. ACCRUED LIABILITIES
	Accrued liabilities as of March 31, 2015 and December 31, 2014 consist of the following (in thousands):
		March 31,		December 31,
		2015		2014
	Eat24 restaurant payable	$	9,740	$	—
	Accrued vacation		5,104		3,972
	Accrued commissions		3,662		4,198
	Accrued employee related expenses		3,575		1,209
	Fixed asset purchase commitments		3,544		6,329
	Accrued employee stock purchase plan liability		3,477		907
	Accrued cost of sales		2,135		2,052
	Accrued payroll tax		1,223		1,251
	Merchant revenue share liability		1,160		1,218
	Accrued income, withholding and business taxes		836		1,354
	Deferred rent		761		1,229
	Other accrued expenses		6,671		5,862
	Total	$	41,888	$	29,581

OTHER_INCOME_EXPENSE_NET

OTHER INCOME (EXPENSE), NET	3 Months Ended
	Mar. 31, 2015
OTHER INCOME (EXPENSE), NET [Abstract]
OTHER INCOME (EXPENSE), NET	9. OTHER INCOME (EXPENSE), NET
	Other income (expense), net for the three months ended March 31, 2015 and 2014 consist of the following (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Interest income	$	300		$	34
	Transaction (loss) on foreign exchange		(171	)		(49	)
	Other non-operating income, net		433			13
	Other income (expense), net	$	562		$	(2	)

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2015
COMMITMENTS AND CONTINGENCIES [Abstract]
COMMITMENTS AND CONTINGENCIES	10. COMMITMENTS AND CONTINGENCIES
	Office Facility Leases — The Company leases its office facilities under operating lease agreements that expire from 2015 to 2025. Certain lease agreements provide for rental payments on a graduated basis. The Company recognizes rent expense on a straight-line basis over the lease period. Rental expense was $6.9 million and $3.6 million for the three months ended March 31, 2015 and 2014, respectively.
	Legal Proceedings — The Company is subject to legal proceedings arising in the ordinary course of business. Although the results of litigation and claims cannot be predicted with certainty, the Company currently does not believe that the final outcome of any of these matters will have a material adverse effect on the Company's business, financial position, results of operations or cash flows.
	In August 2014, two putative class action lawsuits alleging violations of federal securities laws were filed in the U.S. District Court for the Northern District of California, naming as defendants the Company and certain of its officers. The lawsuits allege violations of the Securities Exchange Act of 1934, as amended, by the Company and its officers for allegedly making materially false and misleading statements regarding the Company's business and operations between October 29, 2013 and April 3, 2014. These cases were subsequently consolidated and, in January 2015, plaintiffs filed a consolidated complaint seeking unspecified monetary damages and other relief. On February 6, 2015, the Company and the other named defendants filed a motion to dismiss the consolidated complaint, which the court granted on April 21, 2015 following a hearing on the motion. The plaintiffs have until May 21, 2015 to file an amended complaint.
	On April 23, 2015, a putative class action lawsuit was filed by former Eat24 employees in the Superior Court of California for San Francisco County, naming as defendants Yelp Inc. and Eat24. The lawsuit asserts that the defendants failed to permit meal and rest periods for certain current and former employees working as Eat24 customer support specialists, and alleges violations of the California Labor Code, applicable Industrial Welfare Commission Wage Orders and the California Business and Professions Code. The plaintiffs seek monetary damages in an unspecified amount and injunctive relief.
	Indemnification Agreements — In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to customers, vendors, lessors, business partners and other parties with respect to certain matters, including, but not limited to, losses arising out of breach of such agreements, services to be provided by the Company or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with directors and certain officers and employees that will require the Company to, among other things, indemnify them against certain liabilities that may arise by reason of their status or service as directors, officers or employees.
	While the outcome of these matters cannot be predicted with certainty, the Company does not believe that the outcome of any claims under indemnification arrangements will have a material effect on the Company's financial position, results of operations or cash flows.

STOCKHOLDERS_EQUITY

STOCKHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2015
STOCKHOLDERS' EQUITY [Abstract]
STOCKHOLDERS' EQUITY	11. STOCKHOLDERS' EQUITY
	The following table presents the shares authorized and the shares issued and outstanding as of the periods presented:
			31-Mar-15				31-Dec-14
					Shares				Shares
			Shares		Issued and		Shares		Issued and
			Authorized		Outstanding		Authorized		Outstanding
	Stockholders' equity:
	Class A common stock, $0.000001 par value		200,000,000		65,050,726		200,000,000		63,062,071
	Class B common stock, $0.000001 par value		100,000,000		9,600,608		100,000,000		9,858,511
	Common stock, $0.000001 par value		200,000,000		—		200,000,000		—
	Undesignated Preferred Stock		10,000,000		—		10,000,000		—
	Equity Incentive Plans
	The Company has outstanding awards under three equity incentive plans: the Amended and Restated 2005 Equity Incentive Plan (the “2005 Plan”), the 2011 Equity Incentive Plan (the “2011 Plan”) and the 2012 Equity Incentive Plan, as amended (the “2012 Plan”). In July 2011, the Company terminated the 2005 Plan and provided that no further stock awards were to be granted under the 2005 Plan. All outstanding stock awards under the 2005 Plan continue to be governed by their existing terms. Upon the effectiveness of the underwriting agreement in connection with the Company's initial public offering (“IPO”), all shares that were reserved under the 2011 Plan but not issued were assumed by the 2012 Plan. No further awards will be granted pursuant to the 2011 Plan. All outstanding stock awards under the 2011 Plan continue to be governed by their existing terms. Under the 2012 Plan, the Company has the ability to issue incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock units (“RSUs”), restricted stock awards (“RSAs”), performance units and performance shares. Additionally, the 2012 Plan provides for the grant of performance cash awards to employees, directors and consultants.
	Stock Options
	Stock options granted under the 2012 Plan are granted at a price per share not less than the fair value at date of grant. Options granted to date generally vest either over a four-year period with 25% vesting at the end of one year and the remaining shares vesting monthly thereafter, or over a four-year period with 10% vesting over the first year, 20% vesting over the second year, 30% vesting over the third year and 40% vesting over the fourth year. Options granted are generally exercisable for up to 10 years. A summary of stock option activity for the three months ended March 31, 2015 is as follows:
				Options Outstanding
										Weighted-
										Average
							Weighted-			Remaining			Aggregate
							Average			Contractual			Intrinsic
			Number of				Exercise			Term (in			Value
			Shares				Price			years)			(in thousands)
	Outstanding – January 1, 2015			9,037,935			$	19.64			7.26		$	324,160
	Granted			252,800				53.74
	Exercised			(276,786	)			12.31
	Canceled			(92,628	)			37.34
	Outstanding – March 31, 2015			8,921,321			$	20.65			7.12		$	250,236
	Options vested and expected to vest as of March 31, 2015			8,518,476			$	20.1			7.07		$	242,924
	Options vested and exercisable as of March 31, 2015			4,952,575			$	14.46			6.5		$	165,596
	Aggregate intrinsic value represents the difference between the closing price of the Company's Class A common stock and the exercise price of outstanding, in-the-money options. The total intrinsic value of options exercised was approximately $10.2 million and $52.0 million for the three months ended March 31, 2015 and 2014, respectively. The weighted-average grant date fair value of options granted was $28.16 and $45.83 per share for the three months ended March 31, 2015 and 2014, respectively.
	As of March 31, 2015, total unrecognized compensation costs, adjusted for estimated forfeitures, related to unvested stock options was approximately $47.0 million, which is expected to be recognized over a weighted-average time period of 1.93 years.
	RSUs and RSAs
	The cost of RSUs and RSAs are determined using the fair value of the Company's common stock on the date of grant. RSUs and RSAs generally vest either over a four-year period with 25% vesting at the end of one year and the remaining vesting quarterly or annually thereafter, or over a four-year period with 10% vesting over the first year, 20% vesting over the second year, 30% vesting over the third year and 40% vesting over the fourth year. A summary of RSU and RSA activity for the three months ended March 31, 2015 is as follows:
		Restricted Stock Units						Restricted Stock Awards
					Weighted-
					Average						Weighted-
					Grant						Average Grant
		Number of			Date Fair			Number			Date Fair
		Shares			Value			of Shares			Value
	Unvested—January 1, 2015	1,131,849			$	64.96		30,970			$	9.48
	Granted	650,885				53.81		—				—
	Released	(55,629	)			56.07		(9,687	)			9.16
	Canceled	(84,730	)			62.99		—				—
	Unvested—March 31, 2015	1,642,375			$	60.94		21,283			$	9.63
	As of March 31, 2015, the Company had approximately $75.1 million of unrecognized stock-based compensation expense, net of estimated forfeitures, related to RSUs and RSAs, which will be recognized over the remaining weighted-average vesting period of approximately 3.35 years.
	Employee Stock Purchase Plan
	The ESPP allows eligible employees to purchase shares of the Company's Class A common stock at a discount through payroll deductions of up to 15% of their eligible compensation, subject to any plan limitations during designated offering periods. At the end of each offering period that began prior to December 1, 2014, employees are able to purchase shares at 85% of the lower of the fair market value of the Company's Class A common stock on the first trading day of the offering period or on the last day of the offering period. At the end of each offering period that began December 1, 2014 or later, employees are able to purchase shares at 85% of the fair market value of the Company's Class A common stock on the last day of the offering period. There were no shares purchased by employees under the ESPP during the three months ended March 31, 2015 or 2014. The Company recognized $1.4 million and $1.1 million of stock-based compensation related to the ESPP during the three months ended March 31, 2015 and 2014, respectively.
	Stock-Based Compensation
	The following table summarizes the effects of stock-based compensation related to stock-based awards in the condensed consolidated statements of operations during the periods presented (in thousands):
			Three Months Ended
			March 31,
			2015			2014
	Cost of revenue		$	124		$	150
	Sales and marketing			4,937			3,397
	Product development			5,105			3,042
	General and administrative			3,505			2,867
	Total stock-based compensation in loss before income taxes		$	13,671		$	9,456
	The Company capitalized stock-based compensation as website development costs of $0.7 million and $0.3 million in the three months ended March 31, 2015 and 2014, respectively.

NET_LOSS_PER_SHARE

NET LOSS PER SHARE	12 Months Ended
	Dec. 31, 2014
NET LOSS PER SHARE [Abstract]
NET LOSS PER SHARE	12. NET LOSS PER SHARE
	Basic and diluted net income (loss) per share attributable to common stockholders is presented in conformity with the “two-class method” required for participating securities. Immediately prior to the consummation of the IPO in March 2012, all outstanding shares of preferred stock and common stock were converted to Class B common stock. As a result, shares of Class A and Class B common stock are the only outstanding equity in the Company. The rights of the holders of Class A and Class B common stock are identical, except with respect to voting and conversion. Each share of Class A common stock is entitled to one vote per share and each share of Class B common stock is entitled to 10 votes per share. Shares of Class B common stock may be converted into Class A common stock at any time at the option of the stockholder, and are automatically converted upon sale or transfer to Class A common stock, subject to certain limited exceptions, and in connection with certain other conversion events.
	Basic net income (loss) per share is computed using the weighted-average number of shares of common stock outstanding during the period. Diluted net income per share is computed using the weighted-average number of shares of common stock and, if dilutive, potential shares of common stock outstanding during the period. The Company's potential shares of common stock consist of the incremental shares of common stock issuable upon the exercise of stock options and, to a lesser extent, shares issuable upon the vesting of RSUs, RSAs and purchases related to the ESPP. The dilutive effect of these potential shares of common stock is reflected in diluted earnings per share by application of the treasury stock method. The computation of the diluted net income (loss) per share of Class A common stock assumes the conversion of Class B common stock, while the diluted net income (loss) per share of Class B common stock does not assume the conversion of Class B common stock.
	The undistributed earnings are allocated based on the contractual participation rights of the Class A and Class B common stock as if the earnings for the year have been distributed. As the liquidation and dividend rights are identical, the undistributed earnings are allocated on a proportionate basis. Further, as the conversion of Class B common stock is assumed in the computation of the diluted net income (loss) per share of Class A common stock, the undistributed earnings are equal to net income (loss) for that computation.
	The following table presents the calculation of basic and diluted net loss per share (in thousands, except per share data):
			Three Months Ended March 31,
			2015						2014
			Class A			Class B			Class A			Class B
	Net loss attributable to common stockholders		$	(1,115	)	$	(169	)	$	(2,217	)	$	(418	)
	Basic Shares:
	Weighted-average common shares outstanding			63,976			9,708			59,868			11,303
	Diluted Shares:
	Weighted-average shares used to compute diluted net loss per share			63,976			9,708			59,868			11,303
	Net loss per share attributable to common stockholders
	Basic:		$	(0.02	)	$	(0.02	)	$	(0.04	)	$	(0.04	)
	Diluted:		$	(0.02	)	$	(0.02	)	$	(0.04	)	$	(0.04	)
	The following weighted-average stock-based instruments were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented (in thousands):
		Three Months Ended
		March 31,
		2015		2014
	Stock options	8,921		10,398
	Restricted stock units	1,642		547
	Restricted stock awards	21		64
	Employee stock purchase plan shares	81		89

INCOME_TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2014
INCOME TAXES [Abstract]
INCOME TAXES	13. INCOME TAXES
	The Company is subject to income tax in the United States as well as other tax jurisdictions in which it conducts business. Earnings from non-U.S. activities are subject to local country income tax. The Company does not provide for federal income taxes on the undistributed earnings of its foreign subsidiaries as such earnings are to be reinvested indefinitely. The Company recorded an income tax benefit of $2.4 million and $2.0 million for the three months ended March 31, 2015 and 2014, respectively. The tax benefit for the three months ended March 31, 2015 is due to $2.0 million in U.S. federal and state and foreign income tax benefits, and $0.4 million discrete benefits.
	The primary difference between the effective tax rate and the federal statutory tax rate relates to the valuation allowances on certain of the Company's net operating losses, foreign tax rate differences, meals and entertainment, tax credits, and non-deductible stock-based compensation expense. As of March 31, 2015, the total amount of gross unrecognized tax benefits was $3.4 million, $0.1 million of which is subject to a full valuation allowance and would not affect the Company's effective tax rate if recognized. Included in the balance of unrecognized tax benefits as of March 31, 2015, is $3.3 million of tax benefits that, if recognized, would affect the effective tax rate. As of March 31, 2015, the Company had an immaterial amount related to the accrual of interest and penalties. During the three months ended March 31, 2015, the Company's gross unrecognized tax benefits increased by $0.2 million, all of which would affect the Company's effective tax rate if recognized.
	The Company does not have any tax positions as of March 31, 2015 for which it is reasonably possible that the total amount of gross unrecognized tax benefits will significantly increase or decrease within the next 12 months.

INFORMATION_ABOUT_REVENUE_AND_

INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS	12 Months Ended
	Dec. 31, 2014
INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS [Abstract]
INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS	14. INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS
	The Company considers operating segments to be components of the Company in which separate financial information is available that is evaluated regularly by the Company's chief operating decision maker in deciding how to allocate resources and in assessing performance. The chief operating decision maker for the Company is the Chief Executive Officer. The Chief Executive Officer reviews financial information presented on a consolidated basis, accompanied by information about revenue by product line and geographic region for purposes of allocating resources and evaluating financial performance.
	The Company has one business activity and there are no segment managers who are held accountable for operations, operating results or plans for levels or components below the consolidated unit level. Accordingly, the Company has determined that it has a single operating and reporting segment.
	Revenue by geography is based on the billing address of the customer. The following tables present the Company's net revenue by product line and long-lived assets by geographic region for the periods presented (in thousands):
	Net Revenue
		Three Months Ended
		March 31,
		2015		2014
	Net revenue by product:
	Local advertising	$	98,570	$	65,195
	Brand advertising		6,627		7,455
	Other services		13,311		3,757
	Total net revenue	$	118,508	$	76,407
	During the three months ended March 31, 2015 and 2014, a substantial majority of the Company's revenue was generated in the United States. In addition, no individual customer accounted for 10% or more of consolidated net revenue in either period.
	Long-Lived Assets
		March 31,		December 31,
		2015		2014
	United States	$	68,404	$	73,344
	All Other Countries		5,084		5,900
	Total	$	73,488	$	79,244

DESCRIPTION_OF_BUSINESS_AND_BA1

DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION (Policy)	3 Months Ended
	Mar. 31, 2015
DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION [Abstract]
Basis of Presentation	Basis of Presentation
	The accompanying interim condensed consolidated financial statements are unaudited. These unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these unaudited interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements contained in the Company's Annual Report on Form 10-K filed with the SEC on February 27, 2015 (the “Annual Report”). The unaudited condensed consolidated balance sheet as of December 31, 2014 included herein was derived from the audited consolidated financial statements as of that date, but does not include all disclosures required by GAAP, including certain notes to the financial statements.
	The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, include all adjustments of a normal recurring nature necessary for the fair presentation of the interim periods presented.
Recent Accounting Pronouncements Not Yet Effective	Recent Accounting Pronouncements Not Yet Effective
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update 2014-09, “Revenue from Contracts with Customers” (“ASU 2014-09”), which amended the existing accounting standards for revenue recognition. ASU 2014-09 establishes principles for recognizing revenue upon the transfer of promised goods or services to customers, in an amount that reflects the consideration expected to be received in exchange for those goods or services. The updated standard will replace most existing GAAP revenue recognition guidance when it becomes effective, and permits the use of either the retrospective or cumulative effect transition method. Early adoption of this accounting standard is not permitted. ASU 2014-09 will become effective for the Company in the first quarter of the year ending December 31, 2017. The Company has not yet selected a transition method and is currently evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures.
	In August 2014, FASB issued Accounting Standards Update 2014-15, “Presentation of Financial Statements — Going Concern (Subtopic 205-40).” The new guidance addresses management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern and to provide related footnote disclosures. Management's evaluation should be based on relevant conditions and events that are known and reasonably knowable at the date that the financial statements are issued. The standard will be effective for the first interim period within annual reporting periods beginning after December 15, 2016. Early adoption is permitted. The Company does not expect to early adopt this guidance and does not believe that the adoption of this guidance will have a material impact on its consolidated financial statements.
Principles of Consolidation	Principles of Consolidation
	These unaudited interim condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates
	The preparation of the Company's unaudited interim condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the reporting period. These estimates are based on information available as of the date of the unaudited interim condensed consolidated financial statements; therefore, actual results could differ from management's estimates.

FAIR_VALUE_OF_FINANCIAL_INSTRU1

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
FAIR VALUE OF FINANCIAL INSTRUMENTS [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value		31-Mar-15								31-Dec-14
		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
	Cash Equivalents:
	Money market funds	$	115,506		—		—		115,506	$	208,593	$	—	$	—	$	208,593
	Marketable Securities:
	U.S. government bonds		5,005		—		—		5,005		5,005		—		—		5,005
	Commercial paper		—		33,979				33,979		—		31,965		—		31,965
	Corporate bonds		—		29,267				29,267		—		29,486		—		29,486
	Agency bonds		—		106,829				106,829		—		90,575		—		90,575
	Total cash equivalents and marketable securities	$	120,511	$	170,075	$		$	290,586	$	213,598	$	152,026	$	—	$	365,624
	Current liabilities:
	Contingent consideration liability	$	—	$	—	$	785	$	785	$	—	$	—	$	835	$	835

MARKETABLE_SECURITIES_Tables

MARKETABLE SECURITIES (Tables)	3 Months Ended
	Mar. 31, 2015
MARKETABLE SECURITIES [Abstract]
Schedule of the Fair Value to Amortized Cost Basis of Securities Held-to-Maturity		As of March 31, 2015
				Gross			Gross
				Unrealized			Unrealized
		Amortized Cost		Gains			Losses				Fair Value
	Short-term marketable securities:
	Commercial paper	$	33,979	$	—		$	—			$	33,979
	Corporate bonds		29,280		7			(20	)			29,267
	Agency bonds		90,339		8			(10	)			90,337
	U.S. government bonds		5,005		—			—				5,005
		$	158,603	$	15		$	(30	)		$	158,588
	Long-term marketable securities:
	Agency bonds		16,495		—			(3	)			16,492
		$	16,495	$	—		$	(3	)		$	16,492
	Total marketable securities	$	175,098	$	15		$	(33	)		$	175,080
Schedule of Securities in an Unrealized Loss Position		As of March 31, 2015
		Less Than 12 Months							12 Months or Greater				Total
		Fair Value		Unrealized Loss					Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
	Corporate bonds	$	14,127	$	(20	)			$	—	$	—	$	14,127	$	(20	)
	Agency bonds		67,238		(13	)				—		—		67,238		(13	)
	Total	$	81,365	$	(33	)			$	—	$	—	$	81,365	$	-33

ACQUISITIONS_Tables

ACQUISITIONS (Tables)	3 Months Ended
	Mar. 31, 2015
Eat24 [Member]
Business Acquisition [Line Items]
Schedule of Purchase Price, Assets Aquired and Liabilities Assumed		9-Feb-15
	Fair value of purchase consideration:
	Cash:
	Distributed to Eat24 stockholders	$	56,624
	Held in escrow account		16,500
	Payable on behalf of Eat24 stockholders		1,876
	Total cash		75,000
	Class A common stock:
	Distributed to Eat24 stockholders		46,143
	Held in escrow account		13,015
	Total purchase consideration	$	134,158
	Fair value of net assets acquired:
	Cash and cash equivalents	$	1,578
	Intangibles		39,600
	Goodwill		110,927
	Other assets		6,031
	Total assets acquired		158,136
	Deferred tax liability		(15,207	)
	Other liabilities		(8,771	)
	Total liabilities assumed		(23,978	)
	Net assets acquired	$	134,158
Schedule of Acquired Intangible Assets	Intangible Type		Amount Assigned		Useful Life
	Restaurant relationships		17,400		12.0 years
	Developed technology		7,400		5.0 years
	User relationships		12,000		7.0 years
	Trade name		2,800		4.0 years
	Weighted average				8.6 years
Schedule of Pro Forma Results		Pro Forma for the Three Months Ended March 31,
		2015				2014
	Revenue	$	121,753			$	81,860
	Net loss	$	(2,402	)		$	(3,518	)
	Basic and diluted net loss per share attributable to common stockholders	$	(0.03	)		$	(0.05	)
Restaurant Kritik and Cityvox [Member]
Business Acquisition [Line Items]
Schedule of Purchase Price, Assets Aquired and Liabilities Assumed	Net tangible assets	$	(277	)
	Goodwill		13,995
	Intangible assets		1,546
	Total purchase price (excluding contingent consideration)		15,264
	Contingent consideration		826
	Total purchase price	$	16,090
Schedule of Acquired Intangible Assets	Intangible Type	Useful Life
	Content	5 years
	Developed technology	0.5 years
	Trade name	2 years
	Weighted average	4.3 years

CASH_AND_CASH_EQUIVALENTS_Tabl

CASH AND CASH EQUIVALENTS (Tables)	3 Months Ended
	Mar. 31, 2015
CASH AND CASH EQUIVALENTS [Abstract]
Schedule of Cash and Cash Equivalents		March 31,		December 31,
		2015		2014
	Cash and cash equivalents
	Cash	$	57,123	$	38,719
	Money market funds		115,506		208,593
	Total cash and cash equivalents	$	172,629	$	247,312

PROPERTY_EQUIPMENT_AND_SOFTWAR1

PROPERTY, EQUIPMENT, AND SOFTWARE, NET (Tables)	3 Months Ended
	Mar. 31, 2015
PROPERTY, EQUIPMENT AND SOFTWARE, NET [Abstract]
Schedule of Property, Equipment and Software		March 31,			December 31,
		2015			2014
	Computer equipment	$	20,755		$	19,111
	Software		820			802
	Capitalized website and internal-use software development costs		31,372			27,602
	Furniture and fixtures		8,569			6,621
	Leasehold improvements		39,545			36,991
	Telecommunication		2,623			2,610
	Total		103,684			93,737
	Less accumulated depreciation		(35,090	)		(30,976	)
	Property, equipment and software, net	$	68,594		$	62,761

GOODWILL_AND_INTANGIBLE_ASSETS1

GOODWILL AND INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2015
GOODWILL AND INTANGIBLE ASSETS [Abstract]
Schedule of Goodwill	Balance as of December 31, 2014	$	67,307
	Goodwill measurement period adjustment		51
	Goodwill acquired		110,927
	Effect of currency translation		(6,125	)
	Balance as of March 31, 2015	$	172,160
Schedule of Intangible Assets											Weighted
				Gross					Net		Average
				Carrying		Accumulated			Carrying		Remaining
				Amount		Amortization			Amount		Life
	March 31, 2015:
	Restaurant and user relationships			$	29,400	$	(401	)	$	28,999		9.7 years
	Developed and acquired technology				9,291		(1,131	)		8,160		4.8 years
	Content				3,909		(1,470	)		2,439		3.4 years
	Data licenses and domains				2,291		(497	)		1,794		3.6 years
	Trade name and other				3,347		(552	)		2,795		3.7 years
	Total			$	48,238	$	(4,051	)	$	44,187
												Weighted
				Gross					Net		Average
				Carrying		Accumulated			Carrying		Remaining
				Amount		Amortization			Amount		Life
	December 31, 2014:
	Developed and acquired technology			$	1,963		(861	)	$	1,102		4.2 years
	Advertiser relationships				1,853		(1,853	)		—		0.0 years
	Content				4,299	$	(1,393	)		2,906		3.6 years
	Data licenses and domains				1,977		(326	)		1,651		4.5 years
	Trade name and other				596		(469	)		127		1.4 years
	Total			$	10,688	$	(4,902	)	$	5,786
Schedule of Future Amortization Expense	Year Ending December 31,		Amount
	2015 (from April 1, 2015)		$	5,138
	2016			6,781
	2017			6,638
	2018			6,176
	2019			5,304
	2020 and thereafter			14,150
	Total amortization		$	44,187

ACCRUED_LIABILITIES_Tables

ACCRUED LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2015
ACCRUED LIABILITIES [Abstract]
Schedule of Accrued Liabilities		March 31,		December 31,
		2015		2014
	Eat24 restaurant payable	$	9,740	$	—
	Accrued vacation		5,104		3,972
	Accrued commissions		3,662		4,198
	Accrued employee related expenses		3,575		1,209
	Fixed asset purchase commitments		3,544		6,329
	Accrued employee stock purchase plan liability		3,477		907
	Accrued cost of sales		2,135		2,052
	Accrued payroll tax		1,223		1,251
	Merchant revenue share liability		1,160		1,218
	Accrued income, withholding and business taxes		836		1,354
	Deferred rent		761		1,229
	Other accrued expenses		6,671		5,862
	Total	$	41,888	$	29,581

OTHER_INCOME_EXPENSE_NET_Table

OTHER INCOME (EXPENSE), NET (Tables)	3 Months Ended
	Mar. 31, 2015
OTHER INCOME (EXPENSE), NET [Abstract]
Schedule of Other Income (Expense)		Three Months Ended
		March 31,
		2015			2014
	Interest income	$	300		$	34
	Transaction (loss) on foreign exchange		(171	)		(49	)
	Other non-operating income, net		433			13
	Other income (expense), net	$	562		$	(2	)

STOCKHOLDERS_EQUITY_Tables

STOCKHOLDERS' EQUITY (Tables)	3 Months Ended
	Mar. 31, 2015
STOCKHOLDERS' EQUITY [Abstract]
Schedule of Stock by Class			31-Mar-15				31-Dec-14
					Shares				Shares
			Shares		Issued and		Shares		Issued and
			Authorized		Outstanding		Authorized		Outstanding
	Stockholders' equity:
	Class A common stock, $0.000001 par value		200,000,000		65,050,726		200,000,000		63,062,071
	Class B common stock, $0.000001 par value		100,000,000		9,600,608		100,000,000		9,858,511
	Common stock, $0.000001 par value		200,000,000		—		200,000,000		—
	Undesignated Preferred Stock		10,000,000		—		10,000,000		—
Schedule of Stock Option Activity				Options Outstanding
										Weighted-
										Average
							Weighted-			Remaining			Aggregate
							Average			Contractual			Intrinsic
			Number of				Exercise			Term (in			Value
			Shares				Price			years)			(in thousands)
	Outstanding – January 1, 2015			9,037,935			$	19.64			7.26		$	324,160
	Granted			252,800				53.74
	Exercised			(276,786	)			12.31
	Canceled			(92,628	)			37.34
	Outstanding – March 31, 2015			8,921,321			$	20.65			7.12		$	250,236
	Options vested and expected to vest as of March 31, 2015			8,518,476			$	20.1			7.07		$	242,924
	Options vested and exercisable as of March 31, 2015			4,952,575			$	14.46			6.5		$	165,596
Summary of RSUs and RSAs Activity		Restricted Stock Units						Restricted Stock Awards
					Weighted-
					Average						Weighted-
					Grant						Average Grant
		Number of			Date Fair			Number			Date Fair
		Shares			Value			of Shares			Value
	Unvested—January 1, 2015	1,131,849			$	64.96		30,970			$	9.48
	Granted	650,885				53.81		—				—
	Released	(55,629	)			56.07		(9,687	)			9.16
	Canceled	(84,730	)			62.99		—				—
	Unvested—March 31, 2015	1,642,375			$	60.94		21,283			$	9.63
Schedule of Stock Compensation Expense			Three Months Ended
			March 31,
			2015			2014
	Cost of revenue		$	124		$	150
	Sales and marketing			4,937			3,397
	Product development			5,105			3,042
	General and administrative			3,505			2,867
	Total stock-based compensation in loss before income taxes		$	13,671		$	9,456

NET_LOSS_PER_SHARE_Tables

NET LOSS PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2014
NET LOSS PER SHARE [Abstract]
Schedule of Earnings Per Share			Three Months Ended March 31,
			2015						2014
			Class A			Class B			Class A			Class B
	Net loss attributable to common stockholders		$	(1,115	)	$	(169	)	$	(2,217	)	$	(418	)
	Basic Shares:
	Weighted-average common shares outstanding			63,976			9,708			59,868			11,303
	Diluted Shares:
	Weighted-average shares used to compute diluted net loss per share			63,976			9,708			59,868			11,303
	Net loss per share attributable to common stockholders
	Basic:		$	(0.02	)	$	(0.02	)	$	(0.04	)	$	(0.04	)
	Diluted:		$	(0.02	)	$	(0.02	)	$	(0.04	)	$	(0.04	)
Schedule of Anti-dilutive Securities		Three Months Ended
		March 31,
		2015		2014
	Stock options	8,921		10,398
	Restricted stock units	1,642		547
	Restricted stock awards	21		64
	Employee stock purchase plan shares	81		89

INFORMATION_ABOUT_REVENUE_AND_1

INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS (Tables)	12 Months Ended
	Dec. 31, 2014
INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS [Abstract]
Schedule of Revenue by Product Line		Three Months Ended
		March 31,
		2015		2014
	Net revenue by product:
	Local advertising	$	98,570	$	65,195
	Brand advertising		6,627		7,455
	Other services		13,311		3,757
	Total net revenue	$	118,508	$	76,407
Schedule of Long-Lived Assets by Geographic Region		March 31,		December 31,
		2015		2014
	United States	$	68,404	$	73,344
	All Other Countries		5,084		5,900
	Total	$	73,488	$	79,244

FAIR_VALUE_OF_FINANCIAL_INSTRU2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$115,506	$208,593
Marketable securities	175,080
Total cash equivalents and marketable securities	290,586	365,624
Contingent consideration liability	785	835
U.S. government bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	5,005	5,005
Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	33,979	31,965
Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	29,267	29,486
Agency bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	106,829	90,575
Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	115,506	208,593
Total cash equivalents and marketable securities	120,511	213,598
Contingent consideration liability
Recurring [Member] | Level 1 [Member] | U.S. government bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	5,005	5,005
Recurring [Member] | Level 1 [Member] | Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 1 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 1 [Member] | Agency bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds
Total cash equivalents and marketable securities	170,075	152,026
Contingent consideration liability
Recurring [Member] | Level 2 [Member] | U.S. government bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 2 [Member] | Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	33,979	31,965
Recurring [Member] | Level 2 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	29,267	29,486
Recurring [Member] | Level 2 [Member] | Agency bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	106,829	90,575
Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds
Total cash equivalents and marketable securities
Contingent consideration liability	785	835
Recurring [Member] | Level 3 [Member] | U.S. government bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 3 [Member] | Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 3 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities
Recurring [Member] | Level 3 [Member] | Agency bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities

MARKETABLE_SECURITIES_Schedule

MARKETABLE SECURITIES (Schedule of the Fair Value to Amortized Cost Basis of Securities Held-to-Maturity) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$175,098
Gross Unrealized Gains	15
Gross Unrealized Losses	-33
Fair Value	175,080
Short-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	158,603
Gross Unrealized Gains	15
Gross Unrealized Losses	-30
Fair Value	158,588
Long-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	16,495
Gross Unrealized Gains
Gross Unrealized Losses	-3
Fair Value	16,492
Commercial paper [Member]
Schedule of Held-to-maturity Securities [Line Items]
Fair Value	33,979	31,965
Commercial paper [Member] | Short-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	33,979
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	33,979
Corporate bonds [Member]
Schedule of Held-to-maturity Securities [Line Items]
Fair Value	29,267	29,486
Corporate bonds [Member] | Short-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	29,280
Gross Unrealized Gains	7
Gross Unrealized Losses	-20
Fair Value	29,267
Agency bonds [Member]
Schedule of Held-to-maturity Securities [Line Items]
Fair Value	106,829	90,575
Agency bonds [Member] | Short-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	90,339
Gross Unrealized Gains	8
Gross Unrealized Losses	-10
Fair Value	90,337
Agency bonds [Member] | Long-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	16,495
Gross Unrealized Gains
Gross Unrealized Losses	-3
Fair Value	16,492
U.S. government bonds [Member]
Schedule of Held-to-maturity Securities [Line Items]
Fair Value	5,005	5,005
U.S. government bonds [Member] | Short-term marketable securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	5,005
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	$5,005

MARKETABLE_SECURITIES_Schedule1

MARKETABLE SECURITIES (Schedule of Securities in an Unrealized Loss Position) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Fair Value
Less than 12 months	$81,365
12 months or greater
Total	81,365
Unrealized Loss
Less than 12 months	-33
12 months or greater
Total	-33
Corporate bonds [Member]
Fair Value
Less than 12 months	14,127
12 months or greater
Total	14,127
Unrealized Loss
Less than 12 months	-20
12 months or greater
Total	-20
Agency bonds [Member]
Fair Value
Less than 12 months	67,238
12 months or greater
Total	67,238
Unrealized Loss
Less than 12 months	-13
12 months or greater
Total	($13)

ACQUISITIONS_Summary_of_Purcha

ACQUISITIONS (Summary of Purchase Price and Net Assets Acquired) (Details) (USD $)	3 Months Ended		0 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Feb. 09, 2015	Dec. 31, 2012	Mar. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Contingent liability	$785,000				$785,000	$835,000
Fair value of purchase consideration:
Net cash consideration	71,546,000
Payable on behalf of Eat24 stockholders	1,876,000
Fair value of net assets acquired:
Goodwill	172,160,000				172,160,000	67,307,000
Eat 24 Inc [Member]
Business Acquisition [Line Items]
Acquisition-related transaction costs	200,000
Shares issued or issuable for business acquisition			1,402,844
Fair value of purchase consideration:
Cash consideration			75,000,000
Fair value of common stock			59,200,000
Payable on behalf of Eat24 stockholders			1,876,000
Total purchase price			134,158,000
Fair value of net assets acquired:
Cash and cash equivalents			1,578,000
Intangibles			39,600,000
Goodwill			110,927,000
Other assets			6,031,000
Total assets acquired			158,136,000
Deferred tax liability			-15,207,000
Other liabilities			-8,771,000
Total liabilities assumed			-23,978,000
Net assets acquired			134,158,000
Eat 24 Inc [Member] | Distributed [Member]
Fair value of purchase consideration:
Cash consideration			56,624,000
Fair value of common stock			46,143,000
Eat 24 Inc [Member] | Escrow account [Member]
Business Acquisition [Line Items]
Shares issued or issuable for business acquisition			308,626
Fair value of purchase consideration:
Cash consideration			16,500,000
Fair value of common stock			13,015,000
Qype [Member]
Fair value of purchase consideration:
Cash consideration				24,300,000
Fair value of common stock				23,300,000
Qype [Member] | Escrow account [Member]
Business Acquisition [Line Items]
Funds held in escrow	0				0
Fair value of purchase consideration:
Total purchase price				10,300,000
Fair value of net assets acquired:
Escrow Deposit Released					700,000
Restaurant Kritik and Cityvox [Member]
Business Acquisition [Line Items]
Cash acquired from acquisition						100,000
Acquisition-related transaction costs						600,000
Contingent consideration agreed upon						900,000
Fair value of purchase consideration:
Net cash consideration						15,264,000
Payable on behalf of Eat24 stockholders						826,000
Total purchase price						16,090,000
Fair value of net assets acquired:
Net tangible assets						-277,000
Intangibles						1,546,000
Goodwill						$13,995,000

ACQUISITIONS_Summary_of_Estima

ACQUISITIONS (Summary of Estimated Useful lives of Intangible Assets Acquired ) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Feb. 09, 2015
Eat 24 Inc [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount Assigned			$39,600
Weighted average useful life	8 years 7 months 6 days
Eat 24 Inc [Member] | Restaurant relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount Assigned			17,400
Weighted average useful life	12 years
Eat 24 Inc [Member] | Developed technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount Assigned			7,400
Weighted average useful life	5 years
Eat 24 Inc [Member] | User relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount Assigned			12,000
Weighted average useful life	7 years
Eat 24 Inc [Member] | Trade name [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount Assigned			2,800
Weighted average useful life	4 years
Restaurant Kritik and Cityvox [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount Assigned		$1,546
Weighted average useful life		4 years 3 months 18 days
Restaurant Kritik and Cityvox [Member] | Developed technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life		6 months
Restaurant Kritik and Cityvox [Member] | Trade name [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life		2 years
Restaurant Kritik and Cityvox [Member] | Content [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life		5 years

ACQUISITIONS_Schedule_of_Pro_F

ACQUISITIONS (Schedule of Pro Forma Results) (Details) (Eat24 [Member], USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Eat24 [Member]
Business Acquisition [Line Items]
Revenue	$121,753,000	$81,860,000
Net loss	-2,402,000	-3,518,000
Basic and diluted net loss per share attributable to common stockholders	($0.03)	($0.05)
Revenue	5,300,000
Net loss attributable to Eat24	$400,000

CASH_AND_CASH_EQUIVALENTS_Deta

CASH AND CASH EQUIVALENTS (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Cash and cash equivalents
Cash	$57,123	$38,719
Money market funds	115,506	208,593
Total cash and cash equivalents	172,629	247,312	399,320	389,764
Restricted cash related to letters of credit	$17,899	$17,943

PROPERTY_EQUIPMENT_AND_SOFTWAR2

PROPERTY, EQUIPMENT AND SOFTWARE, NET (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
PROPERTY, EQUIPMENT AND SOFTWARE, NET [Abstract]
Depreciation expense	$5,600,000	$2,800,000
Property, Plant and Equipment [Line Items]
Property, equipment and software	103,684,000		93,737,000
Less accumulated depreciation	-35,090,000		-30,976,000
Property, equipment and software, net	68,594,000		62,761,000
Computer equipment [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and software	20,755,000		19,111,000
Software [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and software	820,000		802,000
Capitalized website and internal-use software development costs [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and software	31,372,000		27,602,000
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and software	8,569,000		6,621,000
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and software	39,545,000		36,991,000
Telecommunication [Member]
Property, Plant and Equipment [Line Items]
Property, equipment and software	$2,623,000		$2,610,000

GOODWILL_AND_INTANGIBLE_ASSETS2

GOODWILL AND INTANGIBLE ASSETS (Schedule of Goodwill) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
GOODWILL AND INTANGIBLE ASSETS [Abstract]
Balance	$67,307
Goodwill measurement period adjustment	51
Goodwill acquired	110,927
Effect of currency translation	-6,125
Balance	$172,160

GOODWILL_AND_INTANGIBLE_ASSETS3

GOODWILL AND INTANGIBLE ASSETS (Schedule of Intangible Assets) (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
GOODWILL AND INTANGIBLE ASSETS [Abstract]
Amortization expense	$1,200,000	$600,000
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	48,238,000		10,688,000
Accumulated Amortization	-4,051,000		-4,902,000
Net Carrying Amount	44,187,000		5,786,000
Restaurant and user relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	29,400,000
Accumulated Amortization	-401,000
Net Carrying Amount	28,999,000
Weighted Average Remaining Life	9 years 8 months 12 days
Developed and acquired technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,291,000		1,963,000
Accumulated Amortization	-1,131,000		-861,000
Net Carrying Amount	8,160,000		1,102,000
Weighted Average Remaining Life	4 years 9 months 18 days		4 years 2 months 12 days
Content [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,909,000		4,299,000
Accumulated Amortization	-1,470,000		-1,393,000
Net Carrying Amount	2,439,000		2,906,000
Weighted Average Remaining Life	3 years 4 months 24 days		3 years 7 months 6 days
Data licenses and domains [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,291,000		1,977,000
Accumulated Amortization	-497,000		-326,000
Net Carrying Amount	1,794,000		1,651,000
Weighted Average Remaining Life	3 years 7 months 6 days		4 years 6 months
Trade name and other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,347,000		596,000
Accumulated Amortization	-552,000		-469,000
Net Carrying Amount	2,795,000		127,000
Weighted Average Remaining Life	3 years 8 months 12 days		1 year 4 months 24 days
Advertiser relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount			1,853,000
Accumulated Amortization			-1,853,000
Net Carrying Amount
Weighted Average Remaining Life			0 years

GOODWILL_AND_INTANGIBLE_ASSETS4

GOODWILL AND INTANGIBLE ASSETS (Schedule of Future Amortization Expense) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Estimated future amortization expense:
2015 (from April 1, 2015)	$5,138
2016	6,781
2017	6,638
2018	6,176
2019	5,304
2020 and thereafter	14,150
Net Carrying Amount	$44,187	$5,786

ACCRUED_LIABILITIES_Details

ACCRUED LIABILITIES (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
ACCRUED LIABILITIES [Abstract]
Eat24 restaurant payable	$9,740
Accrued vacation	5,104	3,972
Accrued commissions	3,662	4,198
Accrued employee related expenses	3,575	1,209
Fixed asset purchase commitments	3,544	6,329
Accrued employee stock purchase plan liability	3,477	907
Accrued cost of sales	2,135	2,052
Accrued payroll tax	1,223	1,251
Merchant revenue share liability	1,160	1,218
Accrued income, withholding and business taxes	836	1,354
Deferred rent	761	1,229
Other accrued expenses	6,671	5,862
Total	$41,888	$29,581

OTHER_INCOME_EXPENSE_NET_Detai

OTHER INCOME (EXPENSE), NET (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
OTHER INCOME (EXPENSE), NET [Abstract]
Interest income	$300	$34
Transaction (loss) on foreign exchange	-171	-49
Other non-operating income, net	433	13
Other income (expense), net	$562	($2)

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Office Facility Lease) (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
COMMITMENTS AND CONTINGENCIES [Abstract]
Rental expense	$6.90	$3.60

STOCKHOLDERS_EQUITY_Award_Comp

STOCKHOLDERS' EQUITY (Award Compensation Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$13,671,000	$9,456,000
Capitalized stock-based compensation	700,000	300,000
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Exercisable period	10 years
Intrinsic value of options exercised	10,200,000	52,000,000
Weighted average grant date fair value	$28.16	$45.83
Unrecognized compensation costs	47,000,000
Unrecognized compensation costs, period for recognition	1 year 11 months 5 days
Stock options [Member] | End of year one [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	25.00%
Stock options [Member] | First year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	10.00%
Stock options [Member] | Second year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	20.00%
Stock options [Member] | Third year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	30.00%
Stock options [Member] | Fourth year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	40.00%
RSUs and RSAs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Unrecognized compensation costs	75,100,000
Unrecognized compensation costs, period for recognition	3 years 4 months 6 days
RSUs and RSAs [Member] | End of year one [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	25.00%
RSUs and RSAs [Member] | First year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	10.00%
RSUs and RSAs [Member] | Second year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	20.00%
RSUs and RSAs [Member] | Third year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	30.00%
RSUs and RSAs [Member] | Fourth year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	40.00%
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Subscription rate of eligible compensation	15.00%
Purchase price, percentage of fair market value	85.00%
Number of shares purchased	0	0
Stock-based compensation	$1,400,000	$1,100,000

STOCKHOLDERS_EQUITY_Schedule_o

STOCKHOLDERS' EQUITY (Schedule of Stock by Class) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Stockholders' equity:
Common stock, par value	$0.00	$0.00
Common stock, Shares Authorized	500,000,000	500,000,000
Common stock, Shares Issued	74,651,334	72,920,582
Common stock, Shares Outstanding	74,651,334	72,920,582
Undesignated Preferred Stock, Shares Authorized	10,000,000	10,000,000
Undesignated Preferred Stock, Shares Issued
Undesignated Preferred Stock, Shares Outstanding
Class A common stock [Member]
Stockholders' equity:
Common stock, par value	$0.00	$0.00
Common stock, Shares Authorized	200,000,000	200,000,000
Common stock, Shares Issued	65,050,726	63,062,071
Common stock, Shares Outstanding	65,050,726	63,062,071
Class B common stock [Member]
Stockholders' equity:
Common stock, par value	$0.00	$0.00
Common stock, Shares Authorized	100,000,000	100,000,000
Common stock, Shares Issued	9,600,608	9,858,511
Common stock, Shares Outstanding	9,600,608	9,858,511
Common stock [Member]
Stockholders' equity:
Common stock, par value	$0.00	$0.00
Common stock, Shares Authorized	200,000,000	200,000,000
Common stock, Shares Issued
Common stock, Shares Outstanding

STOCKHOLDERS_EQUITY_Schedule_o1

STOCKHOLDERS' EQUITY (Schedule of Stock Option Activity) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Number of Shares
Outstanding, beginning balance	9,037,935
Granted	252,800
Exercised	-276,786
Canceled	-92,628
Outstanding, ending balance	8,921,321	9,037,935
Options vested and expected to vest	8,518,476
Options vested and exercisable	4,952,575
Weighted Average Exercise Price
Outstanding, beginning balance	$19.64
Granted	$53.74
Exercised	$12.31
Canceled	$37.34
Outstanding, ending balance	$20.65	$19.64
Options vested and expected to vest	$20.10
Options vested and exercisable	$14.46
Weighted Average Remaining Contractual Term, Outstanding	7 years 1 month 13 days	7 years 3 months 4 days
Weighted Average Remaining Contractual Term, Options vested and expected to vest	7 years 25 days
Weighted Average Remaining Contractual Term, Options vested and exercisable	6 years 6 months
Aggregate Intrinsic Value
Outstanding, beginning balance	$324,160
Outstanding, ending balance	250,236	324,160
Options vested and expected to vest	242,924
Options vested and exercisable	$165,596

STOCKHOLDERS_EQUITY_Schedule_o2

STOCKHOLDERS' EQUITY (Schedule of Restricted Stock Awards and Restricted Stock Units Activity) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015
Restricted Stock Units [Member]
Number of Shares
Unvested, beginning balance	1,131,849
Granted	650,885
Released	-55,629
Canceled	-84,730
Unvested, ending balance	1,642,375
Weighted-Average Grant Date Fair Value
Unvested, beginning balance	$64.96
Granted	$53.81
Released	$56.07
Canceled	$62.99
Unvested, ending balance	$60.94
Restricted Stock Awards [Member]
Number of Shares
Unvested, beginning balance	30,970
Granted
Released	-9,687
Canceled
Unvested, ending balance	21,283
Weighted-Average Grant Date Fair Value
Unvested, beginning balance	$9.48
Granted
Released	$9.16
Canceled
Unvested, ending balance	$9.63

STOCKHOLDERS_EQUITY_Schedule_o3

STOCKHOLDERS' EQUITY (Schedule of Stock-Based Compensation) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation in loss before income taxes	$13,671	$9,456
Cost of revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation in loss before income taxes	124	150
Sales and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation in loss before income taxes	4,937	3,397
Product development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation in loss before income taxes	5,105	3,042
General and administration [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation in loss before income taxes	$3,505	$2,867

NET_LOSS_PER_SHARE_Narrative_D

NET LOSS PER SHARE (Narrative) (Details)	3 Months Ended
	Mar. 31, 2015
Common Class [Member]
Class of Stock [Line Items]
Voting rights	1
Common Class B [Member]
Class of Stock [Line Items]
Voting rights	10

NET_LOSS_PER_SHARE_Schedule_of

NET LOSS PER SHARE (Schedule of Basic and Diluted Net Loss Per Share) (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share Reconciliation [Line Items]
Net loss attributable to common stockholders	($1,284)	($2,635)
Basic Shares:
Weighted-average common shares outstanding	73,684	71,171
Diluted Shares:
Weighted-average shares used to compute diluted net loss per share	73,684	71,171
Net loss per share attributable to common stockholders
Basic:	($0.02)	($0.04)
Diluted:	($0.02)	($0.04)
Class A [Member]
Earnings Per Share Reconciliation [Line Items]
Net loss attributable to common stockholders	-1,115	-2,217
Basic Shares:
Weighted-average common shares outstanding	63,976	59,868
Diluted Shares:
Weighted-average shares used to compute diluted net loss per share	63,976	59,868
Net loss per share attributable to common stockholders
Basic:	($0.02)	($0.04)
Diluted:	($0.02)	($0.04)
Class B [Member]
Earnings Per Share Reconciliation [Line Items]
Net loss attributable to common stockholders	($169)	($418)
Basic Shares:
Weighted-average common shares outstanding	9,708	11,303
Diluted Shares:
Weighted-average shares used to compute diluted net loss per share	9,708	11,303
Net loss per share attributable to common stockholders
Basic:	($0.02)	($0.04)
Diluted:	($0.02)	($0.04)

NET_LOSS_PER_SHARE_Schedule_of1

NET LOSS PER SHARE (Schedule of Anti-Dilutive Employee Stock Awards) (Details)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive awards	8,921	10,398
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive awards	1,642	547
Restricted Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive awards	21	64
ESPP [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive awards	81	89

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
INCOME TAXES [Abstract]
Income tax benefit	($2,403,000)	($1,971,000)
Income tax benefit due to U.S. federal and state and foreign income tax benefit	2,000,000
Income tax benefit discrete benefits	400,000
Unrecognized tax benefits	3,400,000
Unrecognized tax benefits that would not impact the effective tax rate	100,000
Unrecognized tax benefits that would affect the effective tax rate	3,300,000
Unrecognized tax benefits increase	$200,000

INFORMATION_ABOUT_REVENUE_AND_2

INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS (Revenue) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	$118,508	$76,407
Local advertising [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	98,570	65,195
Brand advertising [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	6,627	7,455
Other services [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	$13,311	$3,757

INFORMATION_ABOUT_REVENUE_AND_3

INFORMATION ABOUT REVENUE AND GEOGRAPHIC AREAS (Long-Lived Assets) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$73,488	$79,244
Unites States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	68,404	73,344
All Other Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$5,084	$5,900