Groupon (GRPN) 10-Q 31 Oct 14 2014 Q3 Quarterly report Financial data

Cover_Document

Cover Document	9 Months Ended
	Sep. 30, 2014	Oct. 28, 2014	Oct. 28, 2014
		Common Class A [Member]	Common Class B [Member]
Entity Registrant Name	'Groupon, Inc.	'	'
Entity Central Index Key	'0001490281	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Document Type	'10-Q	'	'
Document Period End Date	30-Sep-14	'	'
Document Fiscal Year Focus	'2014	'	'
Document Fiscal Period Focus	'Q3	'	'
Amendment Flag	'false	'	'
Common Stock, Shares, Outstanding	'	668,957,164	2,399,976

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$855,168	$1,240,472
Accounts receivable, net	124,598	83,673
Deferred income taxes	26,564	27,938
Prepaid expense and other current assets	243,750	210,415
Total current assets	1,250,080	1,562,498
Property, equipment and software, net	170,534	134,423
Goodwill	441,290	220,827
Intangible assets, net	119,810	28,443
Investments	23,639	20,652
Deferred income taxes, non-current	44,709	35,941
Other non-current assets	22,103	39,226
Total Assets	2,072,165	2,042,010
Current liabilities:	'	'
Accounts payable	25,848	27,573
Accrued merchant and supplier payables	754,628	752,943
Accrued expenses	223,677	226,986
Deferred income taxes	44,787	47,558
Other current liabilities	134,116	132,718
Total current liabilities	1,183,056	1,187,778
Deferred income taxes, non-current	9,668	10,853
Other non-current liabilities	151,486	131,697
Total Liabilities	1,344,210	1,330,328
Commitments and contingencies	'	'
Stockholders' Equity	'	'
Additional paid-in capital	1,814,040	1,584,211
Treasury stock, at cost	-190,355	-46,587
Accumulated deficit	-930,748	-848,870
Accumulated other comprehensive income	34,948	24,830
Total Groupon, Inc. Stockholders' Equity	727,955	713,651
Noncontrolling interests	0	-1,969
Total Equity	727,955	711,682
Total Liabilities and Equity	2,072,165	2,042,010
Common Class A [Member]	'	'
Stockholders' Equity	'	'
Common Stock, Value, Issued	70	67
Common Class B [Member]	'	'
Stockholders' Equity	'	'
Common Stock, Value, Issued	0	0
Common Stock [Member]	'	'
Stockholders' Equity	'	'
Common Stock, Value, Issued	$0	$0

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets Parenthetical (USD $)	Sep. 30, 2014	Dec. 31, 2013
Common Stock [Member]	'	'
Condensed Consolidated Balance Sheet Parenthetical [Line Items]	'	'
Common Stock, Par Value	$0.00	$0.00
Common Stock, Shares Authorized	2,010,000,000	2,010,000,000
Common Stock, Shares, Issued	0	0
Common Stock, Shares, Outstanding	0	0
Common Class A [Member]	'	'
Condensed Consolidated Balance Sheet Parenthetical [Line Items]	'	'
Common Stock, Par Value	$0.00	$0.00
Common Stock, Shares Authorized	2,000,000,000	2,000,000,000
Common Stock, Shares, Issued	694,272,530	670,149,976
Common Stock, Shares, Outstanding	668,185,526	665,717,176
Common Class B [Member]	'	'
Condensed Consolidated Balance Sheet Parenthetical [Line Items]	'	'
Common Stock, Par Value	$0.00	$0.00
Common Stock, Shares Authorized	10,000,000	10,000,000
Common Stock, Shares, Issued	2,399,976	2,399,976
Common Stock, Shares, Outstanding	2,399,976	2,399,976
Treasury Stock [Member]	'	'
Condensed Consolidated Balance Sheet Parenthetical [Line Items]	'	'
Treasury Stock, Shares	26,087,004	4,432,800

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenue:	'	'	'	'
Third party and other	$399,803	$394,987	$1,232,173	$1,252,966
Direct	357,251	200,072	1,034,094	552,242
Total revenue	757,054	595,059	2,266,267	1,805,208
Cost of revenue:	'	'	'	'
Third party and other	61,497	54,001	182,226	179,524
Direct	315,413	181,436	928,314	502,359
Total cost of revenue	376,910	235,437	1,110,540	681,883
Gross profit	380,144	359,622	1,155,727	1,123,325
Operating expenses:	'	'	'	'
Marketing	59,935	53,265	203,134	158,319
Selling, general and administrative	325,942	294,074	983,751	904,880
Acquisition-related (benefit) expense, net	-304	-1,529	2,078	-2,276
Total operating expenses	385,573	345,810	1,188,963	1,060,923
(Loss) income from operations	-5,429	13,812	-33,236	62,402
Other (expense) income, net	-20,023	832	-21,886	-9,830
(Loss) income before (benefit) provision for income taxes	-25,452	14,644	-55,122	52,572
(Benefit) provision for income taxes	-6,434	15,936	20,181	62,657
Net loss	-19,018	-1,292	-75,303	-10,085
Net income attributable to noncontrolling interests	-2,190	-1,288	-6,575	-4,061
Net loss attributable to Groupon, Inc.	($21,208)	($2,580)	($81,878)	($14,146)
Net loss per share	'	'	'	'
Basic, net (loss) earnings per share	($0.03)	$0	($0.12)	($0.02)
Diluted, net (loss) earnings per share	($0.03)	$0	($0.12)	($0.02)
Weighted average number of shares outstanding	'	'	'	'
Basic, weighted average number of shares outstanding	669,526,524	666,432,848	675,814,535	662,531,567
Weighted Average Number of Shares Outstanding, Diluted [Abstract]	'	'	'	'
Diluted, weighted average number of shares outstanding	669,526,524	666,432,848	675,814,535	662,531,567

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (Loss) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net loss	($19,018)	($1,292)	($75,303)	($10,085)
Other comprehensive (loss) income, net of tax:	'	'	'	'
Foreign currency translation adjustments	1,827	-1,072	9,899	11,416
Net unrealized loss during the period	-425	-109	-799	-19
Reclassification adjustment for impairment included in net loss	831	0	831	0
Net change in unrealized gain (loss), net	406	-109	32	-19
Other comprehensive income (loss)	2,233	-1,181	9,931	11,397
Comprehensive (loss) income	-16,785	-2,473	-65,372	1,312
Comprehensive income attributable to noncontrolling interests	-2,187	-1,302	-6,388	-4,325
Comprehensive loss attributable to Groupon Inc.	($18,972)	($3,775)	($71,760)	($3,013)

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Loss) Condensed Consolidated Statements of Comprehensive Income (Loss) Parenthetical (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income Parenthetical [Abstract]	'	'	'	'
Tax effects for change in unrealized gain (loss)	$248	($68)	$23	($12)

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Stockholders' Equity (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings (Accumulated Deficit) [Member]	Accumulated Other Comprehensive Income [Member]	Parent [Member]	Noncontrolling Interest [Member]	Total Equity [Member]
In Thousands, except Share data, unless otherwise specified
Beginning Balance, Treasury Stock, Value at Dec. 31, 2013	($46,587)	'	'	($46,587)	'	'	'	'	'
Beginning Balance, Equity at Dec. 31, 2013	711,682	67	1,584,211	'	-848,870	24,830	713,651	-1,969	711,682
Beginning Balance, Shares, Outstanding at Dec. 31, 2013	'	672,549,952	'	'	'	'	'	'	'
Beginning Balance, Treasury Stock, Shares at Dec. 31, 2013	'	'	'	-4,432,800	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'	'
Net loss	-75,303	'	'	'	-81,878	'	-81,878	6,575	-75,303
Foreign currency translation adjustments	9,899	'	'	'	'	10,086	10,086	-187	9,899
Unrealized loss on available-for-sale debt security, net of tax	'	'	'	'	'	32	32	'	32
Common stock issued in connection with acquisition of business, shares	13,825,283	13,825,283	'	'	'	'	'	'	'
Common stock issued in connection with acquisition of business, net of issuance costs	'	2	162,703	'	'	'	162,705	'	162,705
Shares issued to settle liability-classified awards, shares	'	102,180	'	'	'	'	'	'	'
Shares issued to settle liability-classified awards and contingent consideration	1,041	'	1,041	'	'	'	1,041	'	1,041
Purchase of noncontrolling interest, excess of purchase price over value of noncontrolling interest	'	'	-6,310	'	'	'	-6,310	'	'
Purchase of interests in consolidated subsidiaries	'	'	'	'	'	'	'	2,415	'
Purchase of noncontrolling interests in consolidated subsidiaries	'	'	'	'	'	'	'	'	-3,895
Exercise of stock options, shares	'	805,225	'	'	'	'	'	'	'
Exercise of stock options, value	'	'	807	'	'	'	807	'	807
Vesting of restricted stock units, shares	'	12,741,462	'	'	'	'	'	'	'
Vesting of restricted stock units, value	'	1	-1	'	'	'	'	'	'
Shares issued under employee stock purchase plan, shares	'	857,171	'	'	'	'	'	'	'
Shares issued under employee stock purchase plan, value	'	'	5,397	'	'	'	5,397	'	5,397
Tax withholding related to net share settlements of stock-based compensation awards, shares	'	-4,208,767	'	'	'	'	'	'	'
Tax withholding related to net share settlements of stock-based compensation awards, value	'	'	-33,149	'	'	'	-33,149	'	-33,149
Stock-based compensation on equity-classified awards	'	'	97,857	'	'	'	97,857	'	97,857
Excess tax benefits, net of shortfalls, on stock-based compensation awards	'	'	1,484	'	'	'	1,484	'	1,484
Purchases of treasury stock, shares	'	'	'	-21,654,204	'	'	'	'	'
Purchases of treasury stock, value	'	'	'	-143,768	'	'	-143,768	'	-143,768
Partnership distributions to noncontrolling interest holders	'	'	'	'	'	'	'	-6,834	-6,834
Ending Balance, Equity at Sep. 30, 2014	727,955	70	1,814,040	'	-930,748	34,948	727,955	0	727,955
Ending Balance, Treasury Stock, Value at Sep. 30, 2014	($190,355)	'	'	($190,355)	'	'	'	'	'
Ending Balance, Treasury Stock, Shares at Sep. 30, 2014	'	'	'	-26,087,004	'	'	'	'	'
Ending Balance, Shares, Outstanding at Sep. 30, 2014	'	696,672,506	'	'	'	'	'	'	'

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Operating activities	'	'
Net loss	($75,303)	($10,085)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:	'	'
Depreciation and amortization of property, equipment and software	71,476	49,186
Amortization of acquired intangible assets	36,068	16,131
Stock-based compensation	89,958	89,223
Deferred income taxes	-1,956	-1,225
Excess tax benefits on stock-based compensation	-12,573	-12,116
Loss on equity method investments	459	58
Net gain from changes in fair value of contingent consideration	-1,059	-2,276
Impairment of investments	2,036	0
Change in assets and liabilities, net of acquisitions:	'	'
Restricted cash	6,961	-81
Accounts receivable	-29,267	8,999
Prepaid expenses and other current assets	-32,397	13,146
Accounts payable	-8,964	-25,867
Accrued merchant and supplier payables	-61,219	-72,290
Accrued expenses and other current liabilities	-27,091	-27,790
Other, net	44,873	15,144
Net cash provided by operating activities	2,002	40,157
Investing activities	'	'
Purchases of property and equipment and capitalized software	-67,461	-43,574
Acquisitions of businesses, net of acquired cash	-117,303	-6,349
Purchases of investments	-6,704	-19,583
Settlement of liabilities related to purchase of additional interest in consolidated subsidiary	-1,599	-1,959
Purchases of intangible assets	-500	-1,520
Net cash used in investing activities	-193,567	-72,985
Financing activities	'	'
Payments for purchases of treasury stock	-145,395	-7,376
Excess tax benefits on stock-based compensation	12,573	12,116
Taxes paid related to net share settlements of stock-based compensation awards	-32,390	-26,504
Debt issuance costs	-1,029	0
Common stock issuance costs in connection with acquisition of business	-158	0
Payments of contingent consideration from acquisitions	0	-780
Settlements of purchase price obligations related to acquisitions	-3,136	-5,000
Proceeds from stock option exercises and employee stock purchase plan	6,204	6,578
Partnership distribution payments to noncontrolling interest holders	-6,178	-4,286
Payments of capital lease obligations	-3,559	-1,001
Net cash used in financing activities	-173,068	-26,253
Effect of exchange rate changes on cash and cash equivalents	-20,671	-10,351
Net decrease in cash and cash equivalents	-385,304	-69,432
Cash and cash equivalents, beginning of period	1,240,472	1,209,289
Cash and cash equivalents, end of period	855,168	1,139,857
Non-cash investing and financing activities	'	'
Issuance of common stock in connection with acquisition of business	162,862	3,051
Contingent consideration liabilities incurred in connection with acquisitions	4,006	3,567
Equipment acquired under capital lease obligations	18,546	7,377
Shares issued to settle liability-classified awards and contingent consideration	1,041	3,394
Liability for purchases of treasury stock	120	1,638
Liability for purchase consideration	359	0
Liability for purchase of additional interests in consolidated subsidiaries	2,296	0
Accounts payable and accrued expenses related to purchases of property and equipment and capitalized software	$5,508	$1,713

Description_of_Business_and_Ba

Description of Business and Basis of Presentation	9 Months Ended
	Sep. 30, 2014
DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION [Abstract]	'
Description of Business and Basis of Presentation [Text Block]	'
	DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION
	Company Information
	Groupon, Inc. and subsidiaries (the "Company"), which commenced operations in October 2008, operates online local commerce marketplaces throughout the world that connect merchants to consumers by offering goods and services at a discount. The Company also offers deals on products for which it acts as the merchant of record. Customers can access the Company's deal offerings directly through its websites and mobile applications. The Company also sends emails to its subscribers with deal offerings that are targeted by location and personal preferences.
	The Company's operations are organized into three segments: North America, EMEA, which is comprised of Europe, Middle East and Africa, and the remainder of the Company's international operations ("Rest of World"). See Note 12 "Segment Information."
	Unaudited Interim Financial Information
	The Company has prepared the accompanying condensed consolidated financial statements pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC") for interim financial reporting. These condensed consolidated financial statements are unaudited and, in the Company's opinion, include all adjustments, consisting of normal recurring adjustments and accruals, necessary for a fair presentation of the Company's condensed consolidated balance sheets, statements of operations, comprehensive income (loss), cash flows and stockholders' equity for the periods presented. Operating results for the periods presented are not necessarily indicative of the results to be expected for the full year ending December 31, 2014. Certain information and disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles ("U.S. GAAP") have been omitted in accordance with the rules and regulations of the SEC. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes included in the Company's Annual Report on Form 10-K for the year ended December 31, 2013, as filed with the SEC on February 20, 2014.
	Principles of Consolidation
	The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The Company's consolidated financial statements were prepared in accordance with U.S. GAAP and include the assets, liabilities, revenue and expenses of all wholly-owned subsidiaries and majority-owned subsidiaries over which the Company exercises control and variable interest entities for which the Company has determined that it is the primary beneficiary. Outside stockholders' interests in subsidiaries are shown on the condensed consolidated financial statements as "Noncontrolling interests." Equity investments in entities in which the Company does not have a controlling financial interest are accounted for under either the equity method, the cost method or as available-for-sale securities, as appropriate.
	Reclassifications
	Certain reclassifications have been made to the condensed consolidated financial statements of prior periods and the accompanying notes to conform to the current period presentation.
	Use of Estimates
	The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires estimates and assumptions that affect the reported amounts and classifications of assets and liabilities, revenue and expenses, and the related disclosures of contingent liabilities in the condensed consolidated financial statements and accompanying notes. Estimates are utilized for, but not limited to, stock-based compensation, income taxes, valuation of acquired goodwill and intangible assets, investments, customer refunds, contingent liabilities and the useful lives of property, equipment and software and intangible assets. Actual results could differ materially from those estimates.

Business_Combinations_and_Acqu

Business Combinations and Acquisitions of Noncontrolling Interests	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Business Combinations and Acquisitions of Noncontrolling Interests Disclosure [Text Block]	'
	BUSINESS COMBINATIONS
	The Company acquired four businesses during the nine months ended September 30, 2014.  These business combinations were accounted for using the acquisition method, and the results of each of those acquired businesses have been included in the condensed consolidated financial statements beginning on the respective acquisition dates. The fair value of consideration transferred in business combinations is allocated to the tangible and intangible assets acquired and liabilities assumed at the acquisition date, with the remaining unallocated amount recorded as goodwill. The allocations of the acquisition price for recent acquisitions have been prepared on a preliminary basis, and changes to those allocations may occur as a result of final working capital adjustments and tax return filings. Acquired goodwill represents the premium the Company paid over the fair value of the net tangible and intangible assets acquired. The Company paid this premium for a number of reasons, including growing the Company's merchant and customer base, acquiring assembled workforces, expanding its presence in international markets, expanding and advancing its product offerings and enhancing technology capabilities. The goodwill from these business combinations is generally not deductible for tax purposes.
	For the three and nine months ended September 30, 2014, $0.7 million and $3.1 million, respectively, of external transaction costs related to business combinations, primarily consisting of legal and advisory fees, are classified within "Acquisition-related (benefit) expense, net" on the condensed consolidated statements of operations.
	LivingSocial Korea, Inc.
	On January 2, 2014, the Company acquired all of the outstanding equity interests of LivingSocial Korea, Inc., a Korean corporation and holding company of Ticket Monster Inc. ("Ticket Monster"). Ticket Monster is an e-commerce company based in the Republic of Korea that connects merchants to consumers by offering goods and services at a discount. The primary purpose of this acquisition was to grow the Company's merchant and customer base and expand its presence in the Korean e-commerce market. The aggregate acquisition-date fair value of the consideration transferred for the Ticket Monster acquisition totaled $259.4 million, which consisted of the following (in thousands):
	Cash		$	96,496
	Issuance of 13,825,283 shares of Class A common stock		162,862
	Total		$	259,358
	The fair value of the Class A Common Stock issued as consideration was measured based on the stock price upon closing of the transaction on January 2, 2014.
	The following table summarizes the allocation of the aggregate acquisition price of the Ticket Monster acquisition (in thousands):
	Cash and cash equivalents	$	24,768
	Accounts receivable	15,832
	Deferred income taxes	1,264
	Prepaid expenses and other current assets	829
	Property, equipment and software	5,944
	Goodwill	220,592
	Intangible assets:(1)
	Subscriber relationships	57,022
	Merchant relationships	32,176
	Developed technology	571
	Trade name	19,325
	Other non-current assets	3,033
	Total assets acquired	$	381,356
	Accounts payable	$	5,951
	Accrued merchant and supplier payables	82,934
	Accrued expenses	22,700
	Other current liabilities	3,482
	Deferred income taxes, non-current	1,264
	Other non-current liabilities	5,667
	Total liabilities assumed	$	121,998
	Total acquisition price	$	259,358
	-1	The acquired intangible assets have estimated useful lives of between 2 and 5 years.
	Ideeli, Inc.
	On January 13, 2014, the Company acquired all of the outstanding equity interests of Ideeli, Inc. (d/b/a "Ideel"), a fashion flash site based in the United States. The primary purpose of this acquisition was to expand and advance the Company's product offerings. The aggregate acquisition-date fair value of the consideration transferred for the Ideel acquisition totaled $42.7 million, which consisted of the following (in thousands):
	Cash		$	42,339
	Liability for purchase consideration		359
	Total		$	42,698
	The following table summarizes the allocation of the aggregate acquisition price of the Ideel acquisition (in thousands):
	Cash and cash equivalents	$	79
	Accounts receivable	988
	Deferred income taxes	572
	Prepaid expenses and other current assets	22,081
	Property, equipment and software	8,173
	Goodwill	5,379
	Intangible assets:(1)
	Subscriber relationships	5,490
	Brand relationships	7,100
	Trade name	4,500
	Deferred income taxes, non-current	7,753
	Total assets acquired	$	62,115
	Accounts payable	$	1,640
	Accrued supplier payables	4,092
	Accrued expenses	9,118
	Other current liabilities	482
	Deferred income taxes, non-current	332
	Other non-current liabilities	3,753
	Total liabilities assumed	$	19,417
	Total acquisition price	$	42,698
	-1	The acquired intangible assets have estimated useful lives of between 3 and 5 years.
	Other Acquisitions
	The Company acquired two other businesses during the nine months ended September 30, 2014. The primary purpose of these acquisitions was to acquire an experienced workforce, expand and advance product offerings and enhance technology capabilities. The aggregate acquisition-date fair value of the consideration transferred for these acquisitions totaled $7.5 million, which consisted of the following (in thousands):
	Cash		$	3,477
	Contingent consideration		4,006
Total		$	7,483
The following table summarizes the allocation of the aggregate purchase price of these other acquisitions (in thousands):
Net working capital (including acquired cash of $0.2 million)		$	(52	)
Goodwill		6,261
Intangible assets: (1)
Subscriber relationships		560
Brand relationships		579
Developed technology		568
Deferred income taxes, non-current		(433		)
Total acquisition price		$	7,483
-1	Acquired intangible assets have estimated useful lives of between 3 and 5 years.
Pro forma results of operations presented below do not include the results of these other acquisitions because the effects of these acquisitions, individually and in the aggregate, were not material to the Company's condensed consolidated results of operations.
Pro Forma Financial Information
The following unaudited pro forma information presents the combined operating results of the Company for the three and nine months ended September 30, 2013, as if the Company had acquired Ticket Monster and Ideel as of January 1, 2013 (in thousands). Pro forma results of operations have not been presented for the nine months ended September 30, 2014, because the operating results of Ticket Monster and Ideel from January 1, 2014 through their respective acquisition dates were not material to the Company's consolidated results of operations for the nine months ended September 30, 2014. The underlying pro forma results include the historical financial results of the Company and these two acquired businesses adjusted for depreciation and amortization expense associated with the assets acquired. The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and the acquired entities. Accordingly, these unaudited pro forma results are not necessarily indicative of what the actual results of operations of the combined company would have been if the acquisitions had occurred as of January 1, 2013, nor are they indicative of future results of operations.
	Three Months Ended			Nine Months Ended
	September 30, 2013			September 30, 2013
Revenue	$	642,645		$	1,949,406
Net loss	(23,004		)	(79,936		)
The revenue and net loss of Ticket Monster included in our condensed consolidated statements of operations were $42.8 million and $6.4 million for the three months ended September 30, 2014, respectively, and $107.4 million and $30.3 million for the nine months ended September 30, 2014, respectively. The revenue and net loss of Ideel included in our condensed consolidated statements of operations were $20.6 million and $0.5 million for the three months ended September 30, 2014, respectively, and $58.1 million and $3.7 million for the nine months ended September 30, 2014, respectively.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2014
GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]	'
Goodwill and Intangible Assets Disclosure [Text Block]	'
	GOODWILL AND OTHER INTANGIBLE ASSETS
	The following table summarizes the Company's goodwill activity by segment for the nine months ended September 30, 2014 (in thousands):
			North America			EMEA			Rest of World			Consolidated
	Balance as of December 31, 2013		$	85,457		$	115,669		$	19,701		$	220,827
	Goodwill related to acquisitions		11,640			—			220,592			232,232
	Other adjustments(1)		(157		)	(9,578		)	(2,034		)	(11,769		)
	Balance as of September 30, 2014		$	96,940		$	106,091		$	238,259		$	441,290
	-1	Represents the impact of changes in foreign exchange rates on goodwill.
	The following tables summarize the Company's other intangible assets (in thousands):
			30-Sep-14
	Asset Category		Gross Carrying Value			Accumulated Amortization			Net Carrying Value
	Subscriber relationships		$	105,108		$	44,891		$	60,217
	Merchant relationships		40,653			16,522			24,131
	Trade names		29,980			9,800			20,180
	Developed technology		23,415			21,663			1,752
	Brand relationships		7,664			1,103			6,561
	Other intangible assets		17,199			10,230			6,969
	Total		$	224,019		$	104,209		$	119,810
			31-Dec-13
	Asset Category		Gross Carrying Value			Accumulated Amortization			Net Carrying Value
	Subscriber relationships		$	45,541		$	30,866		$	14,675
	Merchant relationships		9,186			7,991			1,195
	Trade names		6,739			6,739			—
	Developed technology		23,038			19,547			3,491
	Other intangible assets		16,776			7,694			9,082
	Total		$	101,280		$	72,837		$	28,443
	Amortization of intangible assets is computed using the straight-line method over their estimated useful lives, which range from 1 to 5 years. Amortization expense related to intangible assets was $11.8 million and $5.3 million for the three months ended September 30, 2014 and 2013, respectively, and $36.1 million and $16.1 million for the nine months ended September 30, 2014 and 2013, respectively. As of September 30, 2014, the Company's estimated future amortization expense related to intangible assets is as follows (in thousands):
	Remaining amounts in 2014		$	11,094
	2015		39,055
	2016		32,912
	2017		18,575
	2018		18,089
	Thereafter		85
	Total		$	119,810

Investments

Investments	9 Months Ended
	Sep. 30, 2014
Investments, All Other Investments [Abstract]	'
Cost and Equity Method Investments Disclosure [Text Block]	'
	INVESTMENTS
	The following table summarizes the Company's investments (dollars in thousands):
		30-Sep-14		Percent Ownership of Voting Stock						December 31, 2013				Percent Ownership of Voting Stock
	Cost and equity method investments:
	Cost method investments	$	15,920	6	%	to	19	%		$	15,788			6	%	to	19	%
	Equity method investments	1,231		21	%	to	50	%		1,690				21	%	to	50	%
	Total cost and equity method investments	17,151								17,478
	Available-for-sale securities:
	Convertible debt securities	2,030								3,174
	Redeemable preferred shares	4,458		19	%	to	23	%		—				19	%
	Total available-for-sale securities	6,488								3,174
	Total investments	$	23,639							$	20,652
	In February 2014, the Company acquired redeemable preferred shares in an online home services company for $4.6 million. The shares are accounted for as available-for-sale securities.
	The following table summarizes the amortized cost, gross unrealized loss and fair value of the Company's available-for-sale securities as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14										December 31, 2013
		Amortized Cost		Gross Unrealized Loss				Fair Value				Amortized Cost				Gross Unrealized Loss			Fair Value
	Available-for-sale securities:
	Convertible debt securities	$	2,030	$	—			$	2,030			$	3,370			$	(196	)	$	3,174
	Redeemable preferred shares	4,599		(141		)		4,458				—				—			—
	Total available-for-sale securities	$	6,629	$	(141	)		$	6,488			$	3,370			$	(196	)	$	3,174
	The Company's investments in available-for-sale securities have been in an unrealized loss position for less than one year as of September 30, 2014.
	Other-Than-Temporary Impairment
	An unrealized loss exists when the current fair value of an investment is less than its amortized cost basis. The Company conducts reviews of all of its investments with unrealized losses on a quarterly basis to evaluate whether those impairments are other-than-temporary. This evaluation, which is performed at the individual investment level, consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as the Company's intent and ability to hold the investment for a period of time that is sufficient to allow for an anticipated recovery in value. Evidence considered in this evaluation includes the amount of the impairment, the length of time that the investment has been impaired, the factors contributing to the impairment, the financial condition and near-term prospects of the investee, recent operating trends and forecasted performance of the investee, market conditions in the geographic area or industry in which the investee operates, and the Company's strategic plans for holding the investment in relation to the period of time expected for an anticipated recovery in value. Additionally, the Company considers whether it intends to sell the investment or whether it is more likely than not that it will be required to sell the investment before recovery of its amortized cost basis. Investments with unrealized losses that are determined to be other-than-temporary are written down to fair value with a charge to earnings. Unrealized losses that are determined to be temporary in nature are not recorded for cost method investments and equity method investments, while such losses are recorded, net of tax, in accumulated other comprehensive income for available-for-sale securities. The Company recorded a $1.3 million other-than-temporary impairment of an investment in the convertible debt securities of a nonpublic entity, which is reported within "Other (expense) income, net" on the condensed consolidated statements of operations for the three and nine months ended September 30, 2014. The Company's investment in Life Media Limited ("F-tuan"), an entity with operations based in China, was written down to zero through an other-than-temporary impairment charge as of December 31, 2013, and continues to have an estimated fair value of zero as of September 30, 2014.

Supplemental_Consolidated_Bala

Supplemental Consolidated Balance Sheet and Statement of Operations Information	9 Months Ended
	Sep. 30, 2014
SUPPLEMENTAL CONSOLIDATED BALANCE SHEET AND STATEMENT OF OPERATIONS INFORMATION [Abstract]	'
Additional Financial Information Disclosures [Text Block]	'
	SUPPLEMENTAL CONSOLIDATED BALANCE SHEETS AND STATEMENTS OF OPERATIONS INFORMATION
	The following table summarizes the Company's other (expense) income, net for the three and nine months ended September 30, 2014 and 2013 (in thousands):
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Interest income	$	409		$	487		$	1,151		$	1,348
	Interest expense	(277		)	(39		)	(444		)	(187		)
	Impairment of investments	(1,448		)	—			(2,036		)	—
	Loss on equity method investments	(91		)	(25		)	(459		)	(58		)
	Foreign exchange (losses) gains, net	(18,638		)	326			(20,108		)	(11,156		)
	Other	22			83			10			223
	Other (expense) income, net	$	(20,023	)	$	832		$	(21,886	)	$	(9,830	)
	The following table summarizes the Company's prepaid expenses and other current assets as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Current portion of unamortized tax effects on intercompany transactions	$	23,377		$	28,502
	Finished goods inventories	57,301			57,097
	Prepaid expenses	42,603			29,404
	Restricted cash	11,056			14,579
	VAT and income taxes receivable	82,804			52,960
	Prepaid marketing	9,832			17,301
	Other	16,777			10,572
	Total prepaid expenses and other current assets	$	243,750		$	210,415
	The following table summarizes the Company's accrued merchant and supplier payables as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Accrued merchant payables	$	575,145		$	518,233
	Accrued supplier payables(1)	179,483			234,710
	Total accrued merchant and supplier payables	$	754,628		$	752,943
	-1	Amounts include payables to suppliers of inventories and providers of shipping and fulfillment services.
	The following table summarizes the Company's accrued expenses as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Marketing	$	11,860		$	12,001
	Refunds reserve	29,221			38,597
	Payroll and benefits	64,751			64,966
	Customer credits	46,297			44,728
	Professional fees	16,902			18,906
	Other	54,646			47,788
	Total accrued expenses	$	223,677		$	226,986
	The following table summarizes the Company's other current liabilities as of September 30, 2014 and December 31, 2013 (in thousands):
		September 30, 2014			December 31, 2013
	Income taxes payable	$	27,020		$	21,994
	VAT payable	30,476			37,627
	Sales taxes payable	6,229			10,412
	Deferred revenue	50,677			47,259
	Other	19,714			15,426
	Total other current liabilities	$	134,116		$	132,718
	The following table summarizes the Company's other non-current liabilities as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Long-term tax liabilities	$	108,233		$	109,286
	Deferred rent	13,216			9,148
	Other	30,037			13,263
	Total other non-current liabilities	$	151,486		$	131,697
	The following table summarizes the components of accumulated other comprehensive income, net of tax, as of September 30, 2014 and December 31, 2013 (in thousands):
		Foreign currency translation adjustments			Unrealized loss on available-for-sale securities, net of tax			Total
	Balance as of December 31, 2013	$	24,952		$	(122	)	$	24,830
	Other comprehensive income (loss) before reclassification adjustments	10,086			(799		)	9,287
	Reclassification adjustment for impairment included in net loss	—			831			831
	Other comprehensive income	10,086			32			10,118
	Balance as of September 30, 2014	$	35,038		$	(90	)	$	34,948
	The effects of amounts reclassified from accumulated other comprehensive income (loss) to net loss for the three and nine months ended September 30, 2014 and 2013 are presented within the following line items in the condensed consolidated statements of operations (in thousands):
		Three Months Ended September 30,						Nine Months Ended September 30,						Condensed Consolidated Statements of Operations Line Item
		2014			2013			2014			2013
	Other-than-temporary impairment of available-for-sale security	$	1,340		$	—		$	1,340		$	—		Other (expense) income, net
	Less: Tax effect	(509		)	—			(509		)	—			(Benefit) provision for income taxes
	Reclassification adjustment	$	831		$	—		$	831		$	—

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies Disclosure [Text Block]	'
	COMMITMENTS AND CONTINGENCIES
	Except as it relates to commitments under operating leases that were assumed in connection with the Ticket Monster and Ideel acquisitions, as described in Note 2, "Business Combinations," the Company's commitments as of September 30, 2014 did not materially change from the amounts set forth in its 2013 Annual Report on Form 10-K. As of September 30, 2014, estimated future payments under operating leases assumed in connection with the Ticket Monster and Ideel acquisitions for each of the next five years and thereafter are as follows (in thousands):
		Operating leases
	2014	$	1,348
	2015	5,148
	2016	4,936
	2017	4,342
	2018	2,631
	Thereafter	11,110
	Total minimum lease payments	$	29,515
	Legal Matters
	From time to time, the Company is party to various legal proceedings incident to the operation of its business. For example, the Company is currently involved in proceedings by stockholders, former employees, merchants, intellectual property infringement suits and suits by customers (individually or as class actions) alleging, among other things, violation of the Credit Card Accountability, Responsibility and Disclosure Act and state laws governing gift cards, stored value cards and coupons. Additionally, the Company is subject to general customer complaints seeking monetary damages, particularly in its Rest of World segment. The following is a brief description of significant legal proceedings.
	On February 8, 2012, the Company issued a press release announcing its expected financial results for the fourth quarter of 2011.  After finalizing its year-end financial statements, the Company announced on March 30, 2012 revised financial results, as well as a material weakness in its internal control over financial reporting related to deficiencies in its financial statement close process.  The revisions resulted in a reduction to fourth quarter 2011 revenue of $14.3 million. The revisions also resulted in an increase to fourth quarter operating expenses that reduced operating income by $30.0 million, net income by $22.6 million and earnings per share by $0.04.  Following this announcement, the Company and several of its current and former directors and officers were named as parties to the following outstanding securities and stockholder derivative lawsuits all arising out of the same alleged events and facts.
	The Company is currently a defendant in a proceeding pursuant to which, on October 29, 2012, a consolidated amended class action complaint was filed against the Company, certain of its directors and officers, and the underwriters that participated in the initial public offering of the Company's Class A common stock.  Originally filed in April 2012, the case is currently pending before the United States District Court for the Northern District of Illinois: In re Groupon, Inc. Securities Litigation. The complaint asserts claims pursuant to Sections 11 and 15 of the Securities Act of 1933 and Sections 10(b) and 20(a) of the Securities Exchange Act of 1934.  Allegations in the consolidated amended complaint include that the Company and its officers and directors made untrue statements or omissions of material fact by issuing inaccurate financial statements for the fiscal quarter and the fiscal year ending December 31, 2011 and by failing to disclose information about the Company's financial controls in the registration statement and prospectus for the Company's initial public offering of Class A common stock and in the Company's subsequently-issued earnings release dated February 8, 2012.  The class action lawsuit seeks an unspecified amount of monetary damages, reimbursement for fees and costs incurred in connection with the actions, including attorneys' fees, and various other forms of monetary and non-monetary relief.  The plaintiff filed an amended motion for class certification on December 4, 2013.  On March 18, 2014, the court entered a scheduling order setting deadlines for fact discovery by March 13, 2015, expert discovery by August 31, 2015, and dispositive motions by October 30, 2015. On May 2, 2014, defendants filed a motion requesting exclusion of the opinions of plaintiff’s proposed market efficiency expert in resolving the motion for class certification. The court held a hearing on the motion to exclude plaintiff’s expert on September 11, 2014 and ordered that the parties file post-hearing briefings. On September 23, 2014, before the parties had commenced the ordered post-hearing briefing, the court entered an order granting plaintiff's motion for class certification. On October 1, 2014, the Company filed a petition for leave to appeal that order in the United States Court of Appeals for the Seventh Circuit. The petition is currently pending.
	In addition, federal and state purported stockholder derivative lawsuits have been filed against certain of the Company's current and former directors and officers.  The federal purported stockholder derivative lawsuit was originally filed in April 2012 and a consolidated stockholder derivative complaint, filed on July 30, 2012, is currently pending in the United States District Court for the Northern District of Illinois: In re Groupon Derivative Litigation.  Plaintiffs assert claims for breach of fiduciary duty and abuse of control.  The state derivative cases are currently pending before the Chancery Division of the Circuit Court of Cook County, Illinois: Orrego v. Lefkofsky, et al., was filed on April 5, 2012; and Kim v. Lefkofsky, et al., was filed on May 25, 2012. The state derivative complaints generally allege that the defendants breached their fiduciary duties by purportedly mismanaging the Company's business by, among other things, failing to utilize proper accounting controls and, in the case of one of the state derivative lawsuits, by engaging in alleged insider trading of the Company's Class A common stock and misappropriating information.  In addition, one state derivative case asserts a claim for unjust enrichment.  The derivative lawsuits purport to seek to recoup for the Company an unspecified amount of monetary damages allegedly sustained by the Company, restitution from defendants, reimbursement for fees and costs incurred in connection with the actions, including attorneys' fees, and various other forms of monetary and non-monetary relief.  On June 20, 2012, the Company and the individual defendants filed a motion requesting that the court stay the consolidated federal derivative action pending resolution of the consolidated federal class actions.  On July 31, 2012, the court granted defendants' motion in part, and stayed the consolidated federal derivative action pending a separate resolution of upcoming motions to dismiss in the consolidated federal class actions.  On June 15, 2012, the state plaintiffs filed a motion to consolidate the state derivative actions, which was granted on July 2, 2012, and on July 5, 2012, the plaintiffs filed a motion for appointment of co-lead plaintiffs and co-lead counsel, which was granted on July 27, 2012.  No consolidated complaint has been filed in the state derivative action. On September 14, 2012, the court granted a motion filed by the parties requesting that the court stay the state derivative actions pending the federal court's resolution of anticipated motions to dismiss in the consolidated federal class action.  On April 18, 2013, the state court appointed a lead plaintiff and approved its selection of lead counsel and local counsel for the purported class. Following entry of the court's order denying defendants' motions to dismiss in In re Groupon Securities Litigation, the courts in both the state and federal derivative actions granted motions requesting that the respective courts extend the litigation stays currently in place pending further developments in In re Groupon, Inc. Securities Litigation.
	The Company intends to defend all of the securities and stockholder derivative lawsuits vigorously.
	In 2010, the Company was named as a defendant in a series of class actions that came to be consolidated into a single case in the U.S. District Court for the Southern District of California.  The consolidated case is referred to as In re Groupon Marketing and Sales Practices Litigation. The Company denies liability, but the parties agreed to settle the litigation for $8.5 million before any determination had been made on the merits or with respect to class certification.  Because the case had been filed as a class action, the parties were required to provide proper notice and obtain court approval for the settlement. During that process, certain individuals asserted various objections to the settlement.  The parties to the case opposed the objections and on December 14, 2012, the district court approved the settlement over the various objections.
	Subsequent to the entry of the order approving settlement, certain of the objectors filed a notice of appeal, contesting the settlement and appealing the matter to the Ninth Circuit of the U.S. Court of Appeals, where the case remains pending.  The Company believes that the settlement is valid and intends to oppose the appeal.  Plaintiffs also maintain that the settlement is valid and will be opposing the appeal.  The settlement, however, is not effective during the pendency of the appeal.  The Company does not know when the appeal will be resolved.  Depending on the outcome of the appeal, it is possible that the settlement will be rejected, or that there will be further proceedings in the appellate court or district court, or that the settlement will be enforced at that time without further objections or proceedings.
	In addition, third parties have from time to time claimed, and others may claim in the future, that the Company has infringed their intellectual property rights. The Company is subject to intellectual property disputes, and expects that it will increasingly be subject to intellectual property infringement claims as its services expand in scope and complexity. The Company has in the past litigated such claims, and several of these claims are currently pending. The Company may also become more vulnerable to third party claims as laws such as the Digital Millennium Copyright Act are interpreted by the courts, and as the Company becomes subject to laws in jurisdictions where the underlying laws with respect to the potential liability of online intermediaries are either unclear or less favorable. The Company believes that additional lawsuits alleging that it has violated patent, copyright or trademark laws will be filed against it. Intellectual property claims, whether meritorious or not, are time consuming and costly to resolve, could require expensive changes in the Company's methods of doing business, or could require it to enter into costly royalty or licensing agreements.
	The Company is also subject to, or in the future may become subject to, a variety of regulatory inquiries across the jurisdictions where the Company conducts its business, including, for example, consumer protection, marketing practices, tax and privacy rules and regulations. Any regulatory actions against the Company, whether meritorious or not, could be time consuming, result in costly litigation, damage awards, injunctive relief or increased costs of doing business through adverse judgment or settlement, require the Company to change its business practices in expensive ways, require significant amounts of management time, result in the diversion of significant operational resources or otherwise harm the Company's business.
	The Company establishes an accrued liability for loss contingencies related to legal and regulatory matters when the loss is both probable and estimable. This accrual represents management's best estimate of probable loss and in such cases, there may be an exposure to loss in excess of the amounts accrued. For each matter described above, there is inherent and significant uncertainties based on, among other factors, the stage of the proceedings, developments in the applicable facts of law, or the lack of a specific damage claim. In addition, for some matters for which a loss is probable or reasonably possible, an estimate of the amount of loss or range of loss is not possible, and we may be unable to estimate the possible loss or range of losses that could potentially result from the application of non-monetary remedies. Currently, the Company is unable to reasonably estimate the amount of reasonably possible losses in excess of the amounts accrued for the securities and stockholder derivative lawsuits. For the remaining matters described above, the Company believes that the amount of reasonably possible losses in excess of the amounts accrued would not have a material adverse effect on its business, consolidated financial position, results of operations or cash flows. The Company's accrued liabilities for loss contingencies related to legal and regulatory matters may change in the future as a result of new developments, including, but not limited to, the occurrence of new legal matters, changes in the law or regulatory environment, adverse of favorable rulings, newly discovered facts relevant to the matter, or changes in the strategy for the matter. Regardless of the outcome, litigation can have an adverse impact on the Company because of defense and settlement costs, diversion of management resources and other factors.
	Indemnifications
	In the normal course of business to facilitate transactions related to its operations, the Company indemnifies certain parties, including employees, lessors, service providers and merchants, with respect to various matters. The Company has agreed to hold certain parties harmless against losses arising from a breach of representations or covenants, or other claims made against those parties. These agreements may limit the time within which an indemnification claim can be made and the amount of the claim. The Company is also subject to increased exposure to various claims as a result of its acquisitions, particularly in cases where the Company is entering into new businesses in connection with such acquisitions. The Company may also become more vulnerable to claims as it expands the range and scope of its services and is subject to laws in jurisdictions where the underlying laws with respect to potential liability are either unclear or less favorable. In addition, the Company has entered into indemnification agreements with its officers and directors, and the Company's bylaws contain similar indemnification obligations to agents.
	It is not possible to determine the maximum potential amount under these indemnification agreements due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement. Historically, any payments that the Company has made under these agreements have not had a material impact on the operating results, financial position or cash flows of the Company.

Revolving_Credit_Agreement_Not

Revolving Credit Agreement (Notes)	9 Months Ended
	Sep. 30, 2014
Line of Credit Facility [Line Items]	'
Debt Disclosure [Text Block]	'
	REVOLVING CREDIT AGREEMENT
	In August 2014, the Company entered into a three-year senior secured revolving credit agreement (the "Credit Agreement") that provides for aggregate principal borrowings of up to $250.0 million. Borrowings under the Credit Agreement bear interest, at the Company's option, at a rate per annum equal to the Alternate Base Rate or Adjusted LIBO Rate (each as defined in the Credit Agreement) plus an additional margin ranging between 0.25% and 2.00%. The Company is required to pay quarterly commitment fees ranging from 0.20% to 0.35% per annum of the average daily amount available under the Credit Agreement. The Credit Agreement also provides for the issuance of up to $45.0 million in letters of credit, provided that the sum of outstanding borrowings and letters of credit do not exceed the maximum funding commitment of $250.0 million.
	The Credit Agreement is secured by substantially all of the Company's and its subsidiaries' tangible and intangible assets, including a pledge of 100% of the outstanding capital stock of substantially all of its direct and indirect domestic subsidiaries and 65% of the shares or equity interests of first-tier foreign subsidiaries and each U.S. entity whose assets substantially consist of capital stock and/or intercompany debt of one or more foreign subsidiaries, subject to certain exceptions. Certain of the Company's domestic subsidiaries are guarantors under the Credit Agreement.
	The Credit Agreement contains various customary restrictive covenants that limit the Company's ability to, among other things: incur additional indebtedness; enter into sale or leaseback transactions; make investments, loans or advances; grant or incur liens on assets; sell assets; engage in mergers, consolidations, liquidations or dissolutions; engage in transactions with affiliates; and make dividend payments. The Credit Agreement requires the Company to maintain compliance with specified financial covenants, comprised of a minimum fixed charge coverage ratio, a maximum leverage ratio, and a minimum liquidity ratio, each as set forth in the Credit Agreement. The Company is also required to maintain, as of the last day of each fiscal quarter, unrestricted cash of at least $400.0 million, including $200.0 million in accounts held with lenders under the Credit Agreement or their affiliates. Non-compliance with these covenants may result in termination of the commitments under the Credit Agreement and any then outstanding borrowings may be declared due and payable immediately. The Company has the right to terminate the Credit Agreement or reduce the available commitments at any time.
	As of September 30, 2014, the Company had no borrowings or letters of credit outstanding under the Credit Agreement and was in compliance with all covenants.

Stockholders_Equity_and_StockB

Stockholders' Equity and Stock-Based Compensation Stockholders' Equity and Stock-Based Compensation (Note)	9 Months Ended
	Sep. 30, 2014
Stockholders' Equity Note [Abstract]	'
Stockholders' Equity and Stock-Based Compensation Note [Text Block]	'
	STOCKHOLDERS' EQUITY AND STOCK-BASED COMPENSATION
	Common Stock
	The Company's Certification of Incorporations authorizes three classes of common stock: Class A common stock, Class B common stock and common stock. No shares of common stock will be issued or outstanding until October 31, 2016, at which time all outstanding shares of Class A common stock and Class B common stock will automatically convert into shares of common stock. In addition, the Company's Certification of Incorporation authorizes shares of undesignated preferred stock, the rights, preferences and privileges of which may be designated from time to time by the Board.
	Share Repurchase Programs
	The Board has authorized the Company to purchase up to $300.0 million of its outstanding Class A common stock through August 2015. The timing and amount of any share repurchases is determined based on market conditions, share price and other factors, and the program may be discontinued or suspended at any time. During the three and nine months ended September 30, 2014, the Company purchased 1,349,712 shares and 21,654,204 shares, respectively, of Class A common stock for an aggregate purchase price of $8.3 million and $143.8 million (including fees and commissions), respectively, under the share repurchase program. As of September 30, 2014, up to $109.6 million of Class A common stock remains available for repurchase under the share repurchase program.
	Groupon, Inc. Stock Plans
	The Groupon, Inc. Stock Plans (the "Plans") are administered by the Compensation Committee of the Board, which determines the number of awards to be issued, the corresponding vesting schedule and the exercise price for options. As of September 30, 2014, 45,500,684 shares were available for future issuance under the Plans.
	The Company recognized stock-based compensation expense of $34.6 million and $26.9 million for the three months ended September 30, 2014 and 2013, respectively, and $90.0 million and $89.2 million for the nine months ended September 30, 2014 and 2013, respectively, related to stock awards issued under the Plans, acquisition-related awards and subsidiary awards. The Company also capitalized $2.8 million and $2.2 million of stock-based compensation for the three months ended September 30, 2014 and 2013, respectively, and $7.9 million and $6.9 million of stock-based compensation for the nine months ended September 30, 2014 and 2013, respectively, in connection with internally-developed software.
	As of September 30, 2014, a total of $230.1 million of unrecognized compensation costs related to unvested stock awards and unvested acquisition-related awards are expected to be recognized over a remaining weighted average period of 1.4 years.
	Employee Stock Purchase Plan
	The Company is authorized to grant up to 10,000,000 shares of common stock under its employee stock purchase plan ("ESPP"). For the nine months ended September 30, 2014 and 2013, 857,171 and 774,288 shares of common stock were issued under the ESPP, respectively.
	Stock Options
	The table below summarizes the stock option activity for the nine months ended September 30, 2014:
			Options		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
								(in thousands) (1)
	Outstanding at December 31, 2013		3,355,054		$	1.11	6.04	$	35,742
	Exercised		(805,225	)	$	1
	Forfeited		(59,489	)	$	2.41
	Outstanding at September 30, 2014		2,490,340		$	1.14	5.3	$	13,796
	Exercisable at September 30, 2014		2,484,486		$	1.13	5.3	$	13,789
	-1	The aggregate intrinsic value of options outstanding and exercisable represents the total pretax intrinsic value (the difference between the fair value of the Company's stock on the last day of each period and the exercise price, multiplied by the number of options where the fair value exceeds the exercise price) that would have been received by the option holders had all option holders exercised their options as of September 30, 2014 and December 31, 2013, respectively.
	Restricted Stock Units
	The table below summarizes activity regarding unvested restricted stock units under the Plans for the nine months ended September 30, 2014:
			Restricted Stock Units		Weighted- Average Grant Date Fair Value (per share)
	Unvested at December 31, 2013		41,648,055		$	8.06
	Granted		22,885,522		$	7.83
	Vested		(12,741,462	)	$	7.97
	Forfeited		(9,586,804	)	$	8
	Unvested at September 30, 2014		42,205,311		$	8.03
	Performance Share Units
	The Company completed its acquisition of Ticket Monster on January 2, 2014, as described in Note 2 "Business Combinations," and approximately 2,000,000 performance share units were granted to certain key employees of that subsidiary. The vesting of these awards into shares of the Company's Class A common stock is contingent upon the subsidiary's achievement of specified financial targets over three annual performance periods for the years ending December 31, 2014, 2015 and 2016 and is subject to continued employment at the end of each performance period. If the financial targets for a performance period are not achieved, no shares will be issued for that performance period. The grant date fair value of the performance share units was $8.07 per share.
	Restricted Stock Awards
	The Company has granted restricted stock awards in connection with prior period business combinations. Compensation expense on these awards is recognized on a straight-line basis over the requisite service periods.
	The table below summarizes activity regarding unvested restricted stock for the nine months ended September 30, 2014:
			Restricted Stock		Weighted- Average Grant Date Fair Value (per share)
	Unvested at December 31, 2013		97,677		$	14
	Vested		(48,890	)	$	14.45
	Forfeited		(13,129	)	$	17.07
	Unvested at September 30, 2014		35,658		$	15.59

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Tax Disclosure [Text Block]	'
	INCOME TAXES
	The Company's tax provision for interim periods is determined using an estimate of its annual effective tax rate, adjusted for discrete items.
	For the three months ended September 30, 2014, the Company recorded an income tax benefit of $6.4 million on pre-tax losses of $25.5 million, for an effective tax rate of 25.3%. For the three months ended September 30, 2013, the Company recorded income tax expense of $15.9 million on pre-tax income of $14.6 million, for an effective tax rate of 108.8%.
	For the nine months ended September 30, 2014, the Company recorded income tax expense of $20.2 million on pre-tax losses of $55.1 million, for an effective tax rate of (36.6)%. For the nine months ended September 30, 2013, the Company recorded income tax expense of $62.7 million on pre-tax income of $52.6 million, for an effective tax rate of 119.2%.
	The Company's U.S. statutory rate is 35%. Significant factors impacting the effective tax rate for the three and nine months ended September 30, 2014 and 2013 included losses in jurisdictions that the Company is not able to benefit due to uncertainty as to the realization of those losses, amortization of the tax effects of intercompany sales of intellectual property and nondeductible stock-based compensation expense. Additionally, the effective tax rate for the three and nine months ended September 30, 2014 included a $7.7 million decrease to the Company's liabilities for uncertain tax positions, as discussed in the following paragraph.
	The Company is currently undergoing income tax audits in multiple jurisdictions. There are many factors, including factors outside of the Company's control, which influence the progress and completion of these audits. For the three and nine months ended September 30, 2014, the Company decreased its liabilities for uncertain tax positions and income tax expense by $7.7 million as a result of new information that impacted its estimates of amounts that are more-likely-than not of being realized upon ultimate settlement. As of September 30, 2014, the Company believes that it is reasonably possible that additional changes of up to $35.5 million in unrecognized tax benefits may occur within the next 12 months upon closing of income tax audits or the expiration of applicable statutes of limitations.
	As of September 30, 2014, unamortized tax effects of intercompany transactions of $23.4 million and $1.5 million are included within "Prepaid expenses and other current assets" and "Other non-current assets," respectively, on the condensed consolidated balance sheet. As of December 31, 2013, unamortized tax effects of intercompany transactions of $28.5 million and $20.4 million are included within "Prepaid expenses and other current assets" and "Other non-current assets," respectively, on the condensed consolidated balance sheet. As of September 30, 2014, the estimated future amortization of the tax effects of intercompany transactions is $6.2 million for the remainder of 2014 and $18.7 million for 2015. These amounts exclude the benefits, if any, for tax deductions in other jurisdictions that the Company may be entitled to as a result of the related intercompany transactions.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2014
FAIR VALUE MEASUREMENTS [Abstract]	'
Fair Value Measurements [Text Block]	'
	FAIR VALUE MEASUREMENTS
	Fair value is defined under U.S. GAAP as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. As such, fair value is a market-based measurement that is determined based on assumptions that market participants would use in pricing an asset or a liability.
	To increase the comparability of fair value measures, the following hierarchy prioritizes the inputs in valuation methodologies used to measure fair value:
	Level 1 - Measurements that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.
	Level 2 - Measurements that include other inputs that are directly or indirectly observable in the marketplace.
	Level 3 - Measurements derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable. These fair value measurements require significant judgment.
	In determining fair value, the Company uses various valuation approaches within the fair value measurement framework. The valuation methodologies used for the Company's assets and liabilities measured at fair value and their classification in the valuation hierarchy are summarized below:
	Cash equivalents - Cash equivalents primarily consist of AAA-rated money market funds with overnight liquidity and no stated maturities. The Company classified cash equivalents as Level 1 due to the short-term nature of these instruments and measured the fair value based on quoted prices in active markets for identical assets.
	Available-for-sale securities - The Company has investments in redeemable preferred shares and convertible debt securities issued by nonpublic entities. The Company measures the fair value of available-for-sale securities using the discounted cash flow method, which is an income approach, and the probability-weighted expected return method, which is an income approach that incorporates probability-weighted outcomes.
	The Company has classified its investments in available-for-sale securities as Level 3 due to the lack of observable market data over fair value inputs such as cash flow projections, discount rates and probability-weightings. Increases in projected cash flows and decreases in discount rates contribute to increases in the estimated fair values of available-for-sale securities, whereas decreases in projected cash flows and increases in discount rates contribute to decreases in their fair values. Additionally, increases in the probabilities of favorable investment outcomes, such as a sale or initial public offering of the investee, and decreases in the probabilities of unfavorable outcomes, such as a default by the investee, contribute to increases in the estimated fair value of available-for-sale securities, whereas decreases in the probabilities of favorable investment outcomes and increases in the probabilities of unfavorable investment outcomes contribute to decreases in their fair values.
	Contingent consideration - The Company has contingent obligations to transfer cash payments to the former owners in conjunction with certain acquisitions if specified financial results are met over future reporting periods. Liabilities for contingent consideration (i.e., earn-outs) are measured at fair value each reporting period, with the acquisition-date fair value included as part of the consideration transferred and subsequent changes in fair value are recorded in earnings within "Acquisition-related (benefit) expense, net" on the condensed consolidated statements of operations.
	The Company uses an income approach to value contingent consideration liabilities, which is determined based on the present value of probability-weighted future cash flows. The Company has generally classified the contingent consideration liabilities as Level 3 due to the lack of relevant observable market data over fair value inputs such as probability-weighting of payment outcomes. Increases in the assessed likelihood of a higher payout under a contingent consideration arrangement contribute to increases in the fair value of the related liability. Conversely, decreases in the assessed likelihood of a higher payout under a contingent consideration arrangement contribute to decreases in the fair value of the related liability. Changes in assumptions could have an impact on the payout of contingent consideration arrangements with a maximum cash payout of $7.3 million as of September 30, 2014.
	The following tables summarize the Company's assets and liabilities that are measured at fair value on a recurring basis (in thousands):
					Fair Value Measurement at Reporting Date Using
	Description	30-Sep-14			Quoted Prices in Active Markets for			Significant Other			Significant
					Identical Assets			Observable			Unobservable
					(Level 1)			Inputs			Inputs
								(Level 2)			(Level 3)
	Assets:
	Cash equivalents	$	440,578		$	440,578		$	—		$	—
	Available-for-sale securities:
	Convertible debt securities	2,030			—			—			2,030
	Redeemable preferred shares	4,458			—			—			4,458
	Liabilities:
	Contingent consideration	2,986			—			—			2,986
					Fair Value Measurement at Reporting Date Using
	Description	31-Dec-13			Quoted Prices in Active Markets for			Significant Other			Significant
					Identical Assets			Observable			Unobservable
					(Level 1)			Inputs			Inputs
								(Level 2)			(Level 3)
	Assets:
	Cash equivalents	$	585,514		$	585,514		$	—		$	—
	Available-for-sale securities:
	Convertible debt securities	3,174			—			—			3,174
	Redeemable preferred shares	—			—			—			—
	Liabilities:
	Contingent consideration	606			—			—			606
	The following table provides a roll-forward of the fair value of recurring Level 3 fair value measurements for the three and nine months ended September 30, 2014 and 2013 (in thousands):
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Assets
	Available-for-sale securities
	Convertible debt securities:
	Beginning Balance	$	2,630		$	3,233		$	3,174		$	3,087
	Total gains (losses) included in other comprehensive income	740			(177		)	196			(31		)
	Total (losses) gains included in other expense (income), net	(1,340		)	—			(1,340		)	—
	Ending Balance	$	2,030		$	3,056		$	2,030		$	3,056
	Unrealized (losses) gains still held(1)	$	(600	)	$	(177	)	$	(1,144	)	$	(31	)
	Redeemable preferred shares:(2)
	Beginning Balance	$	4,544		$	42,539		$	—		$	42,539
	Purchase of redeemable preferred shares	—			—			4,599			—
	Total (losses) gains included in other comprehensive income	(86		)	—			(141		)	—
	Ending Balance	$	4,458		$	42,539		$	4,458		$	42,539
	Unrealized (losses) gains still held(1)	$	(86	)	$	—		$	(141	)	$	—
	Liabilities
	Contingent Consideration:
	Beginning Balance	$	4,006		$	6,854		$	606		$	7,601
	Issuance of contingent consideration in connection with acquisitions	—			3,537			4,006			3,567
	Settlements of contingent consideration liabilities	—			(750		)	(424		)	(780		)
	Reclass to non-fair value liabilities when no longer contingent	—			—			(143		)	—
	Total (gains) losses included in earnings(3)	(1,020		)	(1,529		)	(1,059		)	(2,276		)
	Ending Balance	$	2,986		$	8,112		$	2,986		$	8,112
	Unrealized (gains) losses still held(1)	$	(1,020	)	$	(1,408	)	$	(1,020	)	$	(2,155	)
-1	Represents the unrealized losses or gains recorded in earnings and/or other comprehensive (loss) income during the period for assets and liabilities classified as Level 3 that are still held (or outstanding) at the end of the period.
-2	For the three and nine months ended September 30, 2013, the Company's investments in Life Media Limited (F-tuan) preferred shares were previously classified as cost method investments and have been reclassified to the available-for-sale category in this table. The balance as of September 30, 2013 represents the Company’s investments in F-tuan preferred shares, which were written down to zero through an other-than-temporary impairment charge as of December 31, 2013 and continue to have an estimated fair value of zero as of September 30, 2014. The $4.5 million balance as of September 30, 2014 represents the Company's investment in the preferred shares of an online home services company during the three months ended March 31, 2014, as described in Note 4 "Investments."
-3	Changes in the fair value of contingent consideration liabilities are classified within "Acquisition-related (benefit) expense, net" on the condensed consolidated statements of operations.
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis
Certain assets and liabilities are measured at fair value on a nonrecurring basis, including assets that are written down to fair value as a result of an impairment. The Company did not record any significant nonrecurring fair value measurements after initial recognition during the three and nine months ended September 30, 2014 and 2013.
Estimated Fair Value of Financial Assets and Liabilities Not Measured at Fair Value
The following table presents the carrying amounts and fair values of financial instruments that are not carried at fair value in the condensed consolidated financial statements (in thousands):
		30-Sep-14						31-Dec-13
		Carrying Amount			Fair Value			Carrying Amount			Fair Value
Cost method investments		$	15,920		$	16,037		$	15,788		$	15,573
The fair values of the Company's cost method investments were determined using the market approach or the income approach, depending on the availability of fair value inputs such as financial projections for the investees and market multiples for comparable companies. The Company has classified the fair value measurements of its cost method investments as Level 3 measurements within the fair value hierarchy because they involve significant unobservable inputs such as cash flow projections and discount rates.
The Company's other financial instruments not carried at fair value consist primarily of short term certificates of deposit, accounts receivable, restricted cash, accounts payable, accrued merchant and supplier payables and accrued expenses. The carrying values of these assets and liabilities approximate their respective fair values as of September 30, 2014 and December 31, 2013 due to their short term nature.

Loss_Per_Share_of_Class_A_and_

Loss Per Share of Class A and Class B Common Stock	9 Months Ended
	Sep. 30, 2014
LOSS PER SHARE OF CLASS A AND CLASS B COMMON STOCK [Abstract] [Abstract]	'
Loss Per Share of Class A and Class B Common Stock [Text Block]	'
	LOSS PER SHARE OF CLASS A AND CLASS B COMMON STOCK
	The Company computes loss per share of Class A and Class B common stock using the two-class method. Basic loss per share is computed using the weighted-average number of common shares outstanding during the period. Diluted loss per share is computed using the weighted-average number of common shares and the effect of potentially dilutive equity awards outstanding during the period. Potentially dilutive securities consist of stock options, restricted stock units, unvested restricted stock awards, performance share units and ESPP shares. The dilutive effect of these equity awards are reflected in diluted loss per share by application of the treasury stock method. The computation of the diluted loss per share of Class A common stock assumes the conversion of Class B common stock, if dilutive, while the diluted loss per share of Class B common stock does not assume the conversion of those shares.
	The rights, including the liquidation and dividend rights, of the holders of Class A and Class B common stock are identical, except with respect to voting. Under the two-class method, the undistributed earnings for each period are allocated based on the contractual participation rights of the Class A and Class B common shares as if the earnings for the period had been distributed. As the liquidation and dividend rights are identical, the undistributed earnings are allocated on a proportionate basis. Further, as the Company assumes the conversion of Class B common stock, if dilutive, in the computation of the diluted loss per share of Class A common stock, the undistributed earnings are equal to net income for that computation.
	The following table sets forth the computation of basic and diluted loss per share of Class A and Class B common stock for the three and nine months ended September 30, 2014 and 2013 (in thousands, except share amounts and per share amounts):
			Three Months Ended September 30,												Nine Months Ended September 30,
			2014						2013						2014						2013
			Class A			Class B			Class A			Class B			Class A			Class B			Class A			Class B
	Basic loss per share:
	Numerator
	Allocation of net loss		$	(18,950	)	$	(68	)	$	(1,287	)	$	(5	)	$	(75,035	)	$	(268	)	$	(10,049	)	$	(36	)
	Less: Allocation of net income attributable to noncontrolling interests		2,182			8			1,283			5			6,552			23			4,046			15
	Allocation of net loss attributable to common stockholders		$	(21,132	)	$	(76	)	$	(2,570	)	$	(10	)	$	(81,587	)	$	(291	)	$	(14,095	)	$	(51	)
	Denominator
	Weighted-average common shares outstanding		667,126,548			2,399,976			664,032,872			2,399,976			673,414,559			2,399,976			660,131,591			2,399,976
	Basic loss per share		$	(0.03	)	$	(0.03	)	$	(0.00	)	$	(0.00	)	$	(0.12	)	$	(0.12	)	$	(0.02	)	$	(0.02	)
	Diluted loss per share:
	Numerator
	Allocation of net loss attributable to common stockholders		$	(21,132	)	$	(76	)	$	(2,570	)	$	(10	)	$	(81,587	)	$	(291	)	$	(14,095	)	$	(51	)
	Reallocation of net income attributable to common stockholders as a result of conversion of Class B(1)		—			—			—			—			—			—			—			—
	Allocation of net loss attributable to common stockholders		$	(21,132	)	$	(76	)	$	(2,570	)	$	(10	)	$	(81,587	)	$	(291	)	$	(14,095	)	$	(51	)
	Denominator
	Weighted-average common shares outstanding used in basic computation		667,126,548			2,399,976			664,032,872			2,399,976			673,414,559			2,399,976			660,131,591			2,399,976
	Conversion of Class B(1)		—			—			—			—			—			—			—			—
	Employee stock options(1)		—			—			—			—			—			—			—			—
	Restricted shares and RSUs(1)		—			—			—			—			—			—			—			—
	Weighted-average diluted shares outstanding(1)		667,126,548			2,399,976			664,032,872			2,399,976			673,414,559			2,399,976			660,131,591			2,399,976
	Diluted loss per share		$	(0.03	)	$	(0.03	)	$	(0.00	)	$	(0.00	)	$	(0.12	)	$	(0.12	)	$	(0.02	)	$	(0.02	)
	-1	Conversion of Class B shares into Class A shares and outstanding equity awards have not been reflected in the diluted loss per share calculation for the three and nine months ended September 30, 2014 and 2013 because the effect would be antidilutive.
	The following outstanding equity awards are not included in the diluted loss per share calculation above because they would have had an antidilutive effect:
		Three Months Ended September 30,					Nine Months Ended September 30,
		2014			2013		2014		2013
	Stock options	2,610,764			5,023,559		2,905,390		6,242,363
	Restricted stock units	43,989,496			43,020,496		42,713,167		39,076,490
	Restricted stock	36,988			217,005		58,718		357,339
	ESPP shares	466,271			334,213		528,796		484,184
	Total	47,103,519			48,595,273		46,206,071		46,160,376
	In addition to the antidilutive awards as set forth in the table above, the Company also granted approximately 2,000,000 performance share units in connection with its acquisition of Ticket Monster during the nine months ended September 30, 2014. Contingently issuable shares are excluded from the computation of diluted EPS if, based on current period results, the shares would not be issuable if the end of the reporting period were the end of the contingency period. These outstanding performance share units have been excluded from the table above for the nine months ended September 30, 2014 as the performance conditions would not have been satisfied as of the end of the period.

Segment_Information

Segment Information	9 Months Ended
	Sep. 30, 2014
SEGMENT INFORMATION [Abstract]	'
Segment Reporting Disclosure [Text Block]	'
	SEGMENT INFORMATION
	The company organizes its operations into three segments: North America, EMEA, which is comprised of Europe, Middle East and Africa, and the remainder of the Company's international operations ("Rest of World"). Segment operating results reflect earnings before stock-based compensation, acquisition-related (benefit) expense, net, other (expense) income, net and (benefit) provision for income taxes. Segment information reported in the tables below represents the operating segments of the Company organized in a manner consistent with which separate information is available and for which segment results are evaluated regularly by the Company's chief operating decision-maker in assessing performance and allocating resources.
	Revenue and profit or loss information by reportable segment reconciled to consolidated net loss for the three and nine months ended September 30, 2014 and 2013 were as follows (in thousands):
		Three Months Ended September 30,							Nine Months Ended September 30,
		2014			2013				2014			2013
	North America
	Revenue(1)	$	418,494		$	360,838			$	1,273,487		$	1,077,574
	Segment cost of revenue and operating expenses(2)	405,910			335,670				1,234,973			962,532
	Segment operating income(2)	12,584			25,168				38,514			115,042
	EMEA
	Revenue(1)	230,072			147,950				688,655			491,710
	Segment cost of revenue and operating expenses(2)	207,643			132,346				619,594			417,222
	Segment operating income(2)	22,429			15,604				69,061			74,488
	Rest of World
	Revenue	108,488			86,271				304,125			235,924
	Segment cost of revenue and operating expenses(2)	114,660			87,890				352,900			276,105
	Segment operating loss(2)	(6,172		)	(1,619		)		(48,775		)	(40,181		)
	Consolidated
	Revenue	757,054			595,059				2,266,267			1,805,208
	Segment cost of revenue and operating expenses(2)	728,213			555,906				2,207,467			1,655,859
	Segment operating income(2)	28,841			39,153				58,800			149,349
	Stock-based compensation	34,574			26,870				89,958			89,223
	Acquisition-related (benefit) expense, net	(304		)	(1,529		)		2,078			(2,276		)
	(Loss) income from operations	(5,429		)	13,812				(33,236		)	62,402
	Other (expense) income, net	(20,023		)	832				(21,886		)	(9,830		)
	(Loss) income before (benefit) provision for income taxes	(25,452		)	14,644				(55,122		)	52,572
	(Benefit) provision for income taxes	(6,434		)	15,936				20,181			62,657
	Net loss	$	(19,018	)	$	(1,292	)		$	(75,303	)	$	(10,085	)
	-1	North America includes revenue from the United States of $409.3 million and $349.1 million for the three months ended September 30, 2014 and 2013, respectively, and $1,242.4 million and $1,039.7 million for the nine months ended September 30, 2014 and 2013, respectively. Beginning in September 2013, direct revenue transactions in the EMEA Goods category have been transacted through a Switzerland-based subsidiary. As a result, EMEA includes revenue from Switzerland of $117.7 million and $312.0 million for the three and nine months ended September 30, 2014, respectively.
	-2	Segment cost of revenue and operating expenses and segment operating income (loss) exclude stock-based compensation and acquisition-related (benefit) expense, net. This presentation corresponds to the measure of segment profit or loss that the Company's chief operating decision-maker uses in assessing segment performance and making resource allocation decisions. The following table summarizes the Company's stock-based compensation expense and acquisition-related (benefit) expense, net by reportable segment for the three and nine months ended September 30, 2014 and 2013 (in thousands):
			Three Months Ended September 30,														Nine Months Ended September 30,
			2014							2013							2014						2013
			Stock-based compensation			Acquisition-related				Stock-based compensation			Acquisition-related				Stock-based compensation			Acquisition-related			Stock-based compensation			Acquisition-related
	North America		$	28,493		$	(304	)		$	21,082		$	(984	)		$	74,179		$	1,934		$	69,494		$	(1,364	)
	EMEA		2,687			—				2,616			(545		)		7,187			144			9,082			(912		)
	Rest of World		3,394			—				3,172			—				8,592			—			10,647			—
	Consolidated		$	34,574		$	(304	)		$	26,870		$	(1,529	)		$	89,958		$	2,078		$	89,223		$	(2,276	)
	Acquisition-related (benefit) expense, net for the North America segment includes external transaction costs and gains and losses relating to contingent consideration obligations incurred by U.S. legal entities relating to purchases of businesses that became part of the EMEA and Rest of World segments, which is consistent with the attribution used for internal reporting purposes.
	The following table summarizes the Company's total assets by reportable segment as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	North America (1)	$	978,814		$	1,267,158
	EMEA	543,257			616,126
	Rest of World (1)	550,094			158,726
	Consolidated total assets	$	2,072,165		$	2,042,010
	-1	North America contains assets from the United States of $940.8 million and $1,231.3 million as of September 30, 2014 and December 31, 2013, respectively. Rest of World contains assets from the Republic of Korea, including those assets acquired as a part of our acquisition of Ticket Monster described in Note 2 "Business Combinations," of $395.0 million as of September 30, 2014. There were no other individual countries that represented more than 10% of consolidated total assets as of September 30, 2014 and December 31, 2013, respectively.
	Category Information
	The Company offers goods and services through three primary categories: Local Deals ("Local"), Groupon Goods ("Goods") and Groupon Getaways ("Travel"). The Company also earns advertising revenue, payment processing revenue, point of sale revenue, reservation revenue and commission revenue. Revenue and gross profit from these other sources were previously considered to be distinct from our primary categories and were aggregated with revenue and gross profit from Travel, our smallest category. In recent periods, these other revenue sources have been increasingly viewed by management as a component of the Local category, as they are primarily generated through the Company's relationships with local and national merchants. Accordingly, the Company updated its presentation of category information, effective beginning with the quarter ended March 31, 2014, to include other revenue and gross profit within the Local category in the tables below, and the prior period category information has been retrospectively adjusted to conform to the current period presentation.
	The following table summarizes the Company's third party and other and direct revenue by category for its three reportable segments for the three months ended September 30, 2014 and 2013 (in thousands):
		North America							EMEA							Rest of World						Consolidated
		Three Months Ended September 30,							Three Months Ended September 30,							Three Months Ended September 30,						Three Months Ended September 30,
		2014			2013				2014			2013				2014			2013			2014			2013
	Local (1):
	Third party and other	$	161,912		$	161,306			$	90,002		$	92,141			$	45,085		$	51,900		$	296,999		$	305,347
	Direct	—			1,040				—			—				—			—			—			1,040
	Total	161,912			162,346				90,002			92,141				45,085			51,900			296,999			306,387
	Goods:
	Third party	1,139			3,999				14,750			32,008				37,814			17,215			53,703			53,222
	Direct	237,816			181,915				108,360			9,271				11,075			7,846			357,251			199,032
	Total	238,955			185,914				123,110			41,279				48,889			25,061			410,954			252,254
	Travel:
	Third party	17,627			12,578				16,960			14,530				14,514			9,310			49,101			36,418
	Total revenue	$	418,494		$	360,838			$	230,072		$	147,950			$	108,488		$	86,271		$	757,054		$	595,059
	-1	Includes revenue from deals with local merchants, from deals with national merchants, and through local events.
The following table summarizes the Company's third party and other and direct revenue by category for its three reportable segments for the nine months ended September 30, 2014 and 2013 (in thousands):
	North America							EMEA							Rest of World						Consolidated
	Nine Months Ended							Nine Months Ended							Nine Months Ended						Nine Months Ended
	September 30,							September 30,							September 30,						September 30,
	2014			2013				2014			2013				2014			2013			2014			2013
Local (1):
Third party and other	$	503,659		$	510,284			$	295,607		$	313,959			$	131,610		$	141,163		$	930,876		$	965,406
Direct	—			1,733				—			—				—			—			—			1,733
Total	503,659			512,017				295,607			313,959				131,610			141,163			930,876			967,139
Goods:
Third party	3,859			11,794				49,070			110,821				112,686			50,262			165,615			172,877
Direct	714,157			511,357				296,342			18,903				23,595			20,249			1,034,094			550,509
Total	718,016			523,151				345,412			129,724				136,281			70,511			1,199,709			723,386
Travel:
Third party	51,812			42,406				47,636			48,027				36,234			24,250			135,682			114,683
Total revenue	$	1,273,487		$	1,077,574			$	688,655		$	491,710			$	304,125		$	235,924		$	2,266,267		$	1,805,208
-1	Includes revenue from deals with local merchants, from deals with national merchants, and through local events.
The following table summarizes the Company's gross profit by category for its three reportable segments for the three months ended September 30, 2014 and 2013 (in thousands):
	North America							EMEA							Rest of World						Consolidated
	Three Months Ended							Three Months Ended							Three Months Ended						Three Months Ended
	September 30,							September 30,							September 30,						September 30,
	2014			2013				2014			2013				2014			2013			2014			2013
Local (1):
Third party and other	$	138,189		$	139,737			$	83,956		$	81,808			$	38,592		$	44,435		$	260,737		$	265,980
Direct	—			(847		)		—			—				—			—			—			(847		)
Total	138,189			138,890				83,956			81,808				38,592			44,435			260,737			265,133
Goods:
Third party	951			3,519				12,307			28,036				23,986			11,530			37,244			43,085
Direct	23,002			18,090				19,945			907				(1,109		)	486			41,838			19,483
Total	23,953			21,609				32,252			28,943				22,877			12,016			79,082			62,568
Travel:
Third party	14,000			11,070				15,440			12,930				10,885			7,921			40,325			31,921
Total gross profit	$	176,142		$	171,569			$	131,648		$	123,681			$	72,354		$	64,372		$	380,144		$	359,622
-1	Includes gross profit from deals with local merchants, from deals with national merchants, and through local events.
The following table summarizes the Company's gross profit by category for its three reportable segments for the nine months ended September 30, 2014 and 2013 (in thousands):
	North America							EMEA							Rest of World						Consolidated
	Nine Months Ended							Nine Months Ended							Nine Months Ended						Nine Months Ended
	September 30,							September 30,							September 30,						September 30,
	2014			2013				2014			2013				2014			2013			2014			2013
Local (1):
Third party and other	$	433,485		$	441,787			$	274,395		$	278,515			$	108,958		$	119,810		$	816,838		$	840,112
Direct	—			(790		)		—			—				—			—			—			(790		)
Total	433,485			440,997				274,395			278,515				108,958			119,810			816,838			839,322
Goods:
Third party	3,239			10,317				43,019			96,264				72,101			27,507			118,359			134,088
Direct	56,279			50,725				51,967			(239		)		(2,466		)	187			105,780			50,673
Total	59,518			61,042				94,986			96,025				69,635			27,694			224,139			184,761
Travel:
Third party	42,807			36,472				44,003			42,393				27,940			20,377			114,750			99,242
Total gross profit	$	535,810		$	538,511			$	413,384		$	416,933			$	206,533		$	167,881		$	1,155,727		$	1,123,325
-1	Includes gross profit from deals with local merchants, from deals with national merchants, and through local events.

Description_of_Business_and_Ba1

Description of Business and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Consolidation, Policy [Policy Text Block]	'
	Principles of Consolidation
	The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The Company's consolidated financial statements were prepared in accordance with U.S. GAAP and include the assets, liabilities, revenue and expenses of all wholly-owned subsidiaries and majority-owned subsidiaries over which the Company exercises control and variable interest entities for which the Company has determined that it is the primary beneficiary. Outside stockholders' interests in subsidiaries are shown on the condensed consolidated financial statements as "Noncontrolling interests." Equity investments in entities in which the Company does not have a controlling financial interest are accounted for under either the equity method, the cost method or as available-for-sale securities, as appropriate.
Reclassification, Policy [Policy Text Block]	'
	Reclassifications
	Certain reclassifications have been made to the condensed consolidated financial statements of prior periods and the accompanying notes to conform to the current period presentation.
Use of Estimates, Policy [Policy Text Block]	'
	Use of Estimates
	The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires estimates and assumptions that affect the reported amounts and classifications of assets and liabilities, revenue and expenses, and the related disclosures of contingent liabilities in the condensed consolidated financial statements and accompanying notes. Estimates are utilized for, but not limited to, stock-based compensation, income taxes, valuation of acquired goodwill and intangible assets, investments, customer refunds, contingent liabilities and the useful lives of property, equipment and software and intangible assets. Actual results could differ materially from those estimates.

Business_Combinations_and_Acqu1

Business Combinations and Acquisitions of Noncontrolling Interests (Tables)	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Schedule of Business Acquisitions, Consideration Transferred	'
	The aggregate acquisition-date fair value of the consideration transferred for these acquisitions totaled $7.5 million, which consisted of the following (in thousands):
	Cash		$	3,477
	Contingent consideration		4,006
	Total		$	7,483
	The aggregate acquisition-date fair value of the consideration transferred for the Ticket Monster acquisition totaled $259.4 million, which consisted of the following (in thousands):
	Cash		$	96,496
	Issuance of 13,825,283 shares of Class A common stock		162,862
	Total		$	259,358
	The aggregate acquisition-date fair value of the consideration transferred for the Ideel acquisition totaled $42.7 million, which consisted of the following (in thousands):
	Cash		$	42,339
	Liability for purchase consideration		359
	Total		$	42,698
Schedule of Business Acquisitions, Purchase Price Allocation	'
	The following table summarizes the allocation of the aggregate acquisition price of the Ideel acquisition (in thousands):
	Cash and cash equivalents	$	79
	Accounts receivable	988
	Deferred income taxes	572
	Prepaid expenses and other current assets	22,081
	Property, equipment and software	8,173
	Goodwill	5,379
	Intangible assets:(1)
	Subscriber relationships	5,490
	Brand relationships	7,100
	Trade name	4,500
	Deferred income taxes, non-current	7,753
	Total assets acquired	$	62,115
	Accounts payable	$	1,640
	Accrued supplier payables	4,092
	Accrued expenses	9,118
	Other current liabilities	482
	Deferred income taxes, non-current	332
	Other non-current liabilities	3,753
	Total liabilities assumed	$	19,417
	Total acquisition price	$	42,698
	-1	The acquired intangible assets have estimated useful lives of between 3 and 5 years.
	The following table summarizes the allocation of the aggregate purchase price of these other acquisitions (in thousands):
	Net working capital (including acquired cash of $0.2 million)		$	(52	)
	Goodwill		6,261
	Intangible assets: (1)
	Subscriber relationships		560
	Brand relationships		579
	Developed technology		568
	Deferred income taxes, non-current		(433		)
	Total acquisition price		$	7,483
	-1	Acquired intangible assets have estimated useful lives of between 3 and 5 years.
	The following table summarizes the allocation of the aggregate acquisition price of the Ticket Monster acquisition (in thousands):
	Cash and cash equivalents	$	24,768
	Accounts receivable	15,832
	Deferred income taxes	1,264
	Prepaid expenses and other current assets	829
	Property, equipment and software	5,944
	Goodwill	220,592
	Intangible assets:(1)
	Subscriber relationships	57,022
	Merchant relationships	32,176
	Developed technology	571
	Trade name	19,325
	Other non-current assets	3,033
	Total assets acquired	$	381,356
	Accounts payable	$	5,951
	Accrued merchant and supplier payables	82,934
	Accrued expenses	22,700
	Other current liabilities	3,482
	Deferred income taxes, non-current	1,264
	Other non-current liabilities	5,667
	Total liabilities assumed	$	121,998
	Total acquisition price	$	259,358
	-1	The acquired intangible assets have estimated useful lives of between 2 and 5 years.
Business Acquisition, Pro Forma Information [Table Text Block]	'
	The following unaudited pro forma information presents the combined operating results of the Company for the three and nine months ended September 30, 2013, as if the Company had acquired Ticket Monster and Ideel as of January 1, 2013 (in thousands). Pro forma results of operations have not been presented for the nine months ended September 30, 2014, because the operating results of Ticket Monster and Ideel from January 1, 2014 through their respective acquisition dates were not material to the Company's consolidated results of operations for the nine months ended September 30, 2014. The underlying pro forma results include the historical financial results of the Company and these two acquired businesses adjusted for depreciation and amortization expense associated with the assets acquired. The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and the acquired entities. Accordingly, these unaudited pro forma results are not necessarily indicative of what the actual results of operations of the combined company would have been if the acquisitions had occurred as of January 1, 2013, nor are they indicative of future results of operations.
		Three Months Ended			Nine Months Ended
		September 30, 2013			September 30, 2013
	Revenue	$	642,645		$	1,949,406
	Net loss	(23,004		)	(79,936		)

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2014
GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]	'
Schedule of Goodwill [Table Text Block]	'
	The following table summarizes the Company's goodwill activity by segment for the nine months ended September 30, 2014 (in thousands):
			North America			EMEA			Rest of World			Consolidated
	Balance as of December 31, 2013		$	85,457		$	115,669		$	19,701		$	220,827
	Goodwill related to acquisitions		11,640			—			220,592			232,232
	Other adjustments(1)		(157		)	(9,578		)	(2,034		)	(11,769		)
	Balance as of September 30, 2014		$	96,940		$	106,091		$	238,259		$	441,290
	-1	Represents the impact of changes in foreign exchange rates on goodwill.
Schedule of Finite-Lived Intangible Assets by Major Class [Table Text Block]	'
	The following tables summarize the Company's other intangible assets (in thousands):
			30-Sep-14
	Asset Category		Gross Carrying Value			Accumulated Amortization			Net Carrying Value
	Subscriber relationships		$	105,108		$	44,891		$	60,217
	Merchant relationships		40,653			16,522			24,131
	Trade names		29,980			9,800			20,180
	Developed technology		23,415			21,663			1,752
	Brand relationships		7,664			1,103			6,561
	Other intangible assets		17,199			10,230			6,969
	Total		$	224,019		$	104,209		$	119,810
			31-Dec-13
	Asset Category		Gross Carrying Value			Accumulated Amortization			Net Carrying Value
	Subscriber relationships		$	45,541		$	30,866		$	14,675
	Merchant relationships		9,186			7,991			1,195
	Trade names		6,739			6,739			—
	Developed technology		23,038			19,547			3,491
	Other intangible assets		16,776			7,694			9,082
	Total		$	101,280		$	72,837		$	28,443
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	'
	As of September 30, 2014, the Company's estimated future amortization expense related to intangible assets is as follows (in thousands):
	Remaining amounts in 2014		$	11,094
	2015		39,055
	2016		32,912
	2017		18,575
	2018		18,089
	Thereafter		85
	Total		$	119,810

Investments_Tables

Investments (Tables)	9 Months Ended
	Sep. 30, 2014
Investments, All Other Investments [Abstract]	'
Schedule of Cost and Equity Method Investments [Table Text Block]	'
	The following table summarizes the Company's investments (dollars in thousands):
		30-Sep-14		Percent Ownership of Voting Stock						December 31, 2013				Percent Ownership of Voting Stock
	Cost and equity method investments:
	Cost method investments	$	15,920	6	%	to	19	%		$	15,788			6	%	to	19	%
	Equity method investments	1,231		21	%	to	50	%		1,690				21	%	to	50	%
	Total cost and equity method investments	17,151								17,478
	Available-for-sale securities:
	Convertible debt securities	2,030								3,174
	Redeemable preferred shares	4,458		19	%	to	23	%		—				19	%
	Total available-for-sale securities	6,488								3,174
	Total investments	$	23,639							$	20,652
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]	'
	The following table summarizes the amortized cost, gross unrealized loss and fair value of the Company's available-for-sale securities as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14										December 31, 2013
		Amortized Cost		Gross Unrealized Loss				Fair Value				Amortized Cost				Gross Unrealized Loss			Fair Value
	Available-for-sale securities:
	Convertible debt securities	$	2,030	$	—			$	2,030			$	3,370			$	(196	)	$	3,174
	Redeemable preferred shares	4,599		(141		)		4,458				—				—			—
	Total available-for-sale securities	$	6,629	$	(141	)		$	6,488			$	3,370			$	(196	)	$	3,174

Supplemental_Consolidated_Bala1

Supplemental Consolidated Balance Sheet and Statement of Operations Information (Tables)	9 Months Ended
	Sep. 30, 2014
SUPPLEMENTAL CONSOLIDATED BALANCE SHEET AND STATEMENT OF OPERATIONS INFORMATION [Abstract]	'
Schedule of Other Income (Expense) [Table Text Block]	'
	The following table summarizes the Company's other (expense) income, net for the three and nine months ended September 30, 2014 and 2013 (in thousands):
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Interest income	$	409		$	487		$	1,151		$	1,348
	Interest expense	(277		)	(39		)	(444		)	(187		)
	Impairment of investments	(1,448		)	—			(2,036		)	—
	Loss on equity method investments	(91		)	(25		)	(459		)	(58		)
	Foreign exchange (losses) gains, net	(18,638		)	326			(20,108		)	(11,156		)
	Other	22			83			10			223
	Other (expense) income, net	$	(20,023	)	$	832		$	(21,886	)	$	(9,830	)
Schedule of Prepaid Expenses and Other Current Assets [Table Text Block]	'
	The following table summarizes the Company's prepaid expenses and other current assets as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Current portion of unamortized tax effects on intercompany transactions	$	23,377		$	28,502
	Finished goods inventories	57,301			57,097
	Prepaid expenses	42,603			29,404
	Restricted cash	11,056			14,579
	VAT and income taxes receivable	82,804			52,960
	Prepaid marketing	9,832			17,301
	Other	16,777			10,572
	Total prepaid expenses and other current assets	$	243,750		$	210,415
Schedule of Accrued Merchant and Supplier Payables [Table Text Block]	'
	The following table summarizes the Company's accrued merchant and supplier payables as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Accrued merchant payables	$	575,145		$	518,233
	Accrued supplier payables(1)	179,483			234,710
	Total accrued merchant and supplier payables	$	754,628		$	752,943
	-1	Amounts include payables to suppliers of inventories and providers of shipping and fulfillment services.
Schedule of Accrued Expenses [Table Text Block]	'
	The following table summarizes the Company's accrued expenses as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Marketing	$	11,860		$	12,001
	Refunds reserve	29,221			38,597
	Payroll and benefits	64,751			64,966
	Customer credits	46,297			44,728
	Professional fees	16,902			18,906
	Other	54,646			47,788
	Total accrued expenses	$	223,677		$	226,986
Schedule of Other Current Liabilities [Table Text Block]	'
	The following table summarizes the Company's other current liabilities as of September 30, 2014 and December 31, 2013 (in thousands):
		September 30, 2014			December 31, 2013
	Income taxes payable	$	27,020		$	21,994
	VAT payable	30,476			37,627
	Sales taxes payable	6,229			10,412
	Deferred revenue	50,677			47,259
	Other	19,714			15,426
	Total other current liabilities	$	134,116		$	132,718
Schedule of Other Liabilities, Noncurrent [Table Text Block]	'
	The following table summarizes the Company's other non-current liabilities as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	Long-term tax liabilities	$	108,233		$	109,286
	Deferred rent	13,216			9,148
	Other	30,037			13,263
	Total other non-current liabilities	$	151,486		$	131,697
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	'
	The following table summarizes the components of accumulated other comprehensive income, net of tax, as of September 30, 2014 and December 31, 2013 (in thousands):
		Foreign currency translation adjustments			Unrealized loss on available-for-sale securities, net of tax			Total
	Balance as of December 31, 2013	$	24,952		$	(122	)	$	24,830
	Other comprehensive income (loss) before reclassification adjustments	10,086			(799		)	9,287
	Reclassification adjustment for impairment included in net loss	—			831			831
	Other comprehensive income	10,086			32			10,118
	Balance as of September 30, 2014	$	35,038		$	(90	)	$	34,948
	The effects of amounts reclassified from accumulated other comprehensive income (loss) to net loss for the three and nine months ended September 30, 2014 and 2013 are presented within the following line items in the condensed consolidated statements of operations (in thousands):
		Three Months Ended September 30,						Nine Months Ended September 30,						Condensed Consolidated Statements of Operations Line Item
		2014			2013			2014			2013
	Other-than-temporary impairment of available-for-sale security	$	1,340		$	—		$	1,340		$	—		Other (expense) income, net
	Less: Tax effect	(509		)	—			(509		)	—			(Benefit) provision for income taxes
	Reclassification adjustment	$	831		$	—		$	831		$	—

Commitments_and_Contingencies_

Commitments and Contingencies Operating Leases (Tables)	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	'
	As of September 30, 2014, estimated future payments under operating leases assumed in connection with the Ticket Monster and Ideel acquisitions for each of the next five years and thereafter are as follows (in thousands):
		Operating leases
	2014	$	1,348
	2015	5,148
	2016	4,936
	2017	4,342
	2018	2,631
	Thereafter	11,110
	Total minimum lease payments	$	29,515

Stockholders_Equity_and_StockB1

Stockholders' Equity and Stock-Based Compensation Stockholders' Equity Tables (Tables)	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]	'
	The table below summarizes the stock option activity for the nine months ended September 30, 2014:
			Options		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
								(in thousands) (1)
	Outstanding at December 31, 2013		3,355,054		$	1.11	6.04	$	35,742
	Exercised		(805,225	)	$	1
	Forfeited		(59,489	)	$	2.41
	Outstanding at September 30, 2014		2,490,340		$	1.14	5.3	$	13,796
	Exercisable at September 30, 2014		2,484,486		$	1.13	5.3	$	13,789
	-1	The aggregate intrinsic value of options outstanding and exercisable represents the total pretax intrinsic value (the difference between the fair value of the Company's stock on the last day of each period and the exercise price, multiplied by the number of options where the fair value exceeds the exercise price) that would have been received by the option holders had all option holders exercised their options as of September 30, 2014 and December 31, 2013, respectively.
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]	'
	The table below summarizes activity regarding unvested restricted stock units under the Plans for the nine months ended September 30, 2014:
			Restricted Stock Units		Weighted- Average Grant Date Fair Value (per share)
	Unvested at December 31, 2013		41,648,055		$	8.06
	Granted		22,885,522		$	7.83
	Vested		(12,741,462	)	$	7.97
	Forfeited		(9,586,804	)	$	8
	Unvested at September 30, 2014		42,205,311		$	8.03
Schedule of Nonvested Restricted Stock Units Activity, Acquisition [Table Text Block]	'
	The table below summarizes activity regarding unvested restricted stock for the nine months ended September 30, 2014:
			Restricted Stock		Weighted- Average Grant Date Fair Value (per share)
	Unvested at December 31, 2013		97,677		$	14
	Vested		(48,890	)	$	14.45
	Forfeited		(13,129	)	$	17.07
	Unvested at September 30, 2014		35,658		$	15.59

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2014
FAIR VALUE MEASUREMENTS [Abstract]	'
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	'
	The following tables summarize the Company's assets and liabilities that are measured at fair value on a recurring basis (in thousands):
					Fair Value Measurement at Reporting Date Using
	Description	30-Sep-14			Quoted Prices in Active Markets for			Significant Other			Significant
					Identical Assets			Observable			Unobservable
					(Level 1)			Inputs			Inputs
								(Level 2)			(Level 3)
	Assets:
	Cash equivalents	$	440,578		$	440,578		$	—		$	—
	Available-for-sale securities:
	Convertible debt securities	2,030			—			—			2,030
	Redeemable preferred shares	4,458			—			—			4,458
	Liabilities:
	Contingent consideration	2,986			—			—			2,986
					Fair Value Measurement at Reporting Date Using
	Description	31-Dec-13			Quoted Prices in Active Markets for			Significant Other			Significant
					Identical Assets			Observable			Unobservable
					(Level 1)			Inputs			Inputs
								(Level 2)			(Level 3)
	Assets:
	Cash equivalents	$	585,514		$	585,514		$	—		$	—
	Available-for-sale securities:
	Convertible debt securities	3,174			—			—			3,174
	Redeemable preferred shares	—			—			—			—
	Liabilities:
	Contingent consideration	606			—			—			606
Fair Value, Assets and Liabilities, Reconciliation of Level 3 Inputs [Table Text Block]	'
	The following table provides a roll-forward of the fair value of recurring Level 3 fair value measurements for the three and nine months ended September 30, 2014 and 2013 (in thousands):
		Three Months Ended September 30,						Nine Months Ended September 30,
		2014			2013			2014			2013
	Assets
	Available-for-sale securities
	Convertible debt securities:
	Beginning Balance	$	2,630		$	3,233		$	3,174		$	3,087
	Total gains (losses) included in other comprehensive income	740			(177		)	196			(31		)
	Total (losses) gains included in other expense (income), net	(1,340		)	—			(1,340		)	—
	Ending Balance	$	2,030		$	3,056		$	2,030		$	3,056
	Unrealized (losses) gains still held(1)	$	(600	)	$	(177	)	$	(1,144	)	$	(31	)
	Redeemable preferred shares:(2)
	Beginning Balance	$	4,544		$	42,539		$	—		$	42,539
	Purchase of redeemable preferred shares	—			—			4,599			—
	Total (losses) gains included in other comprehensive income	(86		)	—			(141		)	—
	Ending Balance	$	4,458		$	42,539		$	4,458		$	42,539
	Unrealized (losses) gains still held(1)	$	(86	)	$	—		$	(141	)	$	—
	Liabilities
	Contingent Consideration:
	Beginning Balance	$	4,006		$	6,854		$	606		$	7,601
	Issuance of contingent consideration in connection with acquisitions	—			3,537			4,006			3,567
	Settlements of contingent consideration liabilities	—			(750		)	(424		)	(780		)
	Reclass to non-fair value liabilities when no longer contingent	—			—			(143		)	—
	Total (gains) losses included in earnings(3)	(1,020		)	(1,529		)	(1,059		)	(2,276		)
	Ending Balance	$	2,986		$	8,112		$	2,986		$	8,112
	Unrealized (gains) losses still held(1)	$	(1,020	)	$	(1,408	)	$	(1,020	)	$	(2,155	)
	-1	Represents the unrealized losses or gains recorded in earnings and/or other comprehensive (loss) income during the period for assets and liabilities classified as Level 3 that are still held (or outstanding) at the end of the period.
	-2	For the three and nine months ended September 30, 2013, the Company's investments in Life Media Limited (F-tuan) preferred shares were previously classified as cost method investments and have been reclassified to the available-for-sale category in this table. The balance as of September 30, 2013 represents the Company’s investments in F-tuan preferred shares, which were written down to zero through an other-than-temporary impairment charge as of December 31, 2013 and continue to have an estimated fair value of zero as of September 30, 2014. The $4.5 million balance as of September 30, 2014 represents the Company's investment in the preferred shares of an online home services company during the three months ended March 31, 2014, as described in Note 4 "Investments."
	-3	Changes in the fair value of contingent consideration liabilities are classified within "Acquisition-related (benefit) expense, net" on the condensed consolidated statements of operations.
Fair Value of Financial Assets and Liabilities not Measured at Fair Value [Table Text Block]	'
	The following table presents the carrying amounts and fair values of financial instruments that are not carried at fair value in the condensed consolidated financial statements (in thousands):
			30-Sep-14						31-Dec-13
			Carrying Amount			Fair Value			Carrying Amount			Fair Value
	Cost method investments		$	15,920		$	16,037		$	15,788		$	15,573

Loss_Per_Share_of_Class_A_and_1

Loss Per Share of Class A and Class B Common Stock (Tables)	9 Months Ended
	Sep. 30, 2014
LOSS PER SHARE OF CLASS A AND CLASS B COMMON STOCK [Abstract] [Abstract]	'
Schedule of Earnings per Share, Basic and Diluted [Table Text Block]	'
	The following table sets forth the computation of basic and diluted loss per share of Class A and Class B common stock for the three and nine months ended September 30, 2014 and 2013 (in thousands, except share amounts and per share amounts):
			Three Months Ended September 30,												Nine Months Ended September 30,
			2014						2013						2014						2013
			Class A			Class B			Class A			Class B			Class A			Class B			Class A			Class B
	Basic loss per share:
	Numerator
	Allocation of net loss		$	(18,950	)	$	(68	)	$	(1,287	)	$	(5	)	$	(75,035	)	$	(268	)	$	(10,049	)	$	(36	)
	Less: Allocation of net income attributable to noncontrolling interests		2,182			8			1,283			5			6,552			23			4,046			15
	Allocation of net loss attributable to common stockholders		$	(21,132	)	$	(76	)	$	(2,570	)	$	(10	)	$	(81,587	)	$	(291	)	$	(14,095	)	$	(51	)
	Denominator
	Weighted-average common shares outstanding		667,126,548			2,399,976			664,032,872			2,399,976			673,414,559			2,399,976			660,131,591			2,399,976
	Basic loss per share		$	(0.03	)	$	(0.03	)	$	(0.00	)	$	(0.00	)	$	(0.12	)	$	(0.12	)	$	(0.02	)	$	(0.02	)
	Diluted loss per share:
	Numerator
	Allocation of net loss attributable to common stockholders		$	(21,132	)	$	(76	)	$	(2,570	)	$	(10	)	$	(81,587	)	$	(291	)	$	(14,095	)	$	(51	)
	Reallocation of net income attributable to common stockholders as a result of conversion of Class B(1)		—			—			—			—			—			—			—			—
	Allocation of net loss attributable to common stockholders		$	(21,132	)	$	(76	)	$	(2,570	)	$	(10	)	$	(81,587	)	$	(291	)	$	(14,095	)	$	(51	)
	Denominator
	Weighted-average common shares outstanding used in basic computation		667,126,548			2,399,976			664,032,872			2,399,976			673,414,559			2,399,976			660,131,591			2,399,976
	Conversion of Class B(1)		—			—			—			—			—			—			—			—
	Employee stock options(1)		—			—			—			—			—			—			—			—
	Restricted shares and RSUs(1)		—			—			—			—			—			—			—			—
	Weighted-average diluted shares outstanding(1)		667,126,548			2,399,976			664,032,872			2,399,976			673,414,559			2,399,976			660,131,591			2,399,976
	Diluted loss per share		$	(0.03	)	$	(0.03	)	$	(0.00	)	$	(0.00	)	$	(0.12	)	$	(0.12	)	$	(0.02	)	$	(0.02	)
	-1	Conversion of Class B shares into Class A shares and outstanding equity awards have not been reflected in the diluted loss per share calculation for the three and nine months ended September 30, 2014 and 2013 because the effect would be antidilutive.
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	'
	The following outstanding equity awards are not included in the diluted loss per share calculation above because they would have had an antidilutive effect:
		Three Months Ended September 30,					Nine Months Ended September 30,
		2014			2013		2014		2013
	Stock options	2,610,764			5,023,559		2,905,390		6,242,363
	Restricted stock units	43,989,496			43,020,496		42,713,167		39,076,490
	Restricted stock	36,988			217,005		58,718		357,339
	ESPP shares	466,271			334,213		528,796		484,184
	Total	47,103,519			48,595,273		46,206,071		46,160,376

Segment_Information_Tables

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2014
SEGMENT INFORMATION [Abstract]	'
Schedule of Segment Reporting Information, by Segment [Table Text Block]	'
	Revenue and profit or loss information by reportable segment reconciled to consolidated net loss for the three and nine months ended September 30, 2014 and 2013 were as follows (in thousands):
		Three Months Ended September 30,							Nine Months Ended September 30,
		2014			2013				2014			2013
	North America
	Revenue(1)	$	418,494		$	360,838			$	1,273,487		$	1,077,574
	Segment cost of revenue and operating expenses(2)	405,910			335,670				1,234,973			962,532
	Segment operating income(2)	12,584			25,168				38,514			115,042
	EMEA
	Revenue(1)	230,072			147,950				688,655			491,710
	Segment cost of revenue and operating expenses(2)	207,643			132,346				619,594			417,222
	Segment operating income(2)	22,429			15,604				69,061			74,488
	Rest of World
	Revenue	108,488			86,271				304,125			235,924
	Segment cost of revenue and operating expenses(2)	114,660			87,890				352,900			276,105
	Segment operating loss(2)	(6,172		)	(1,619		)		(48,775		)	(40,181		)
	Consolidated
	Revenue	757,054			595,059				2,266,267			1,805,208
	Segment cost of revenue and operating expenses(2)	728,213			555,906				2,207,467			1,655,859
	Segment operating income(2)	28,841			39,153				58,800			149,349
	Stock-based compensation	34,574			26,870				89,958			89,223
	Acquisition-related (benefit) expense, net	(304		)	(1,529		)		2,078			(2,276		)
	(Loss) income from operations	(5,429		)	13,812				(33,236		)	62,402
	Other (expense) income, net	(20,023		)	832				(21,886		)	(9,830		)
	(Loss) income before (benefit) provision for income taxes	(25,452		)	14,644				(55,122		)	52,572
	(Benefit) provision for income taxes	(6,434		)	15,936				20,181			62,657
	Net loss	$	(19,018	)	$	(1,292	)		$	(75,303	)	$	(10,085	)
	-1	North America includes revenue from the United States of $409.3 million and $349.1 million for the three months ended September 30, 2014 and 2013, respectively, and $1,242.4 million and $1,039.7 million for the nine months ended September 30, 2014 and 2013, respectively. Beginning in September 2013, direct revenue transactions in the EMEA Goods category have been transacted through a Switzerland-based subsidiary. As a result, EMEA includes revenue from Switzerland of $117.7 million and $312.0 million for the three and nine months ended September 30, 2014, respectively.
	-2	Segment cost of revenue and operating expenses and segment operating income (loss) exclude stock-based compensation and acquisition-related (benefit) expense, net. This presentation corresponds to the measure of segment profit or loss that the Company's chief operating decision-maker uses in assessing segment performance and making resource allocation decisions. The following table summarizes the Company's stock-based compensation expense and acquisition-related (benefit) expense, net by reportable segment for the three and nine months ended September 30, 2014 and 2013 (in thousands):
			Three Months Ended September 30,														Nine Months Ended September 30,
			2014							2013							2014						2013
			Stock-based compensation			Acquisition-related				Stock-based compensation			Acquisition-related				Stock-based compensation			Acquisition-related			Stock-based compensation			Acquisition-related
	North America		$	28,493		$	(304	)		$	21,082		$	(984	)		$	74,179		$	1,934		$	69,494		$	(1,364	)
	EMEA		2,687			—				2,616			(545		)		7,187			144			9,082			(912		)
	Rest of World		3,394			—				3,172			—				8,592			—			10,647			—
	Consolidated		$	34,574		$	(304	)		$	26,870		$	(1,529	)		$	89,958		$	2,078		$	89,223		$	(2,276	)
	Acquisition-related (benefit) expense, net for the North America segment includes external transaction costs and gains and losses relating to contingent consideration obligations incurred by U.S. legal entities relating to purchases of businesses that became part of the EMEA and Rest of World segments, which is consistent with the attribution used for internal reporting purposes.
Stock Based Compensation and Acquisition Related by Segment [Table Text Block]	'
	Segment cost of revenue and operating expenses and segment operating income (loss) exclude stock-based compensation and acquisition-related (benefit) expense, net. This presentation corresponds to the measure of segment profit or loss that the Company's chief operating decision-maker uses in assessing segment performance and making resource allocation decisions. The following table summarizes the Company's stock-based compensation expense and acquisition-related (benefit) expense, net by reportable segment for the three and nine months ended September 30, 2014 and 2013 (in thousands):
			Three Months Ended September 30,														Nine Months Ended September 30,
			2014							2013							2014						2013
			Stock-based compensation			Acquisition-related				Stock-based compensation			Acquisition-related				Stock-based compensation			Acquisition-related			Stock-based compensation			Acquisition-related
	North America		$	28,493		$	(304	)		$	21,082		$	(984	)		$	74,179		$	1,934		$	69,494		$	(1,364	)
	EMEA		2,687			—				2,616			(545		)		7,187			144			9,082			(912		)
	Rest of World		3,394			—				3,172			—				8,592			—			10,647			—
	Consolidated		$	34,574		$	(304	)		$	26,870		$	(1,529	)		$	89,958		$	2,078		$	89,223		$	(2,276	)
	Acquisition-related (benefit) expense, net for the North America segment includes external transaction costs and gains and losses relating to contingent consideration obligations incurred by U.S. legal entities relating to purchases of businesses that became part of the EMEA and Rest of World segments, which is consistent with the attribution used for internal reporting purposes.
Schedule of Segment Assets [Table Text Block]	'
	The following table summarizes the Company's total assets by reportable segment as of September 30, 2014 and December 31, 2013 (in thousands):
		30-Sep-14			31-Dec-13
	North America (1)	$	978,814		$	1,267,158
	EMEA	543,257			616,126
	Rest of World (1)	550,094			158,726
	Consolidated total assets	$	2,072,165		$	2,042,010
	-1	North America contains assets from the United States of $940.8 million and $1,231.3 million as of September 30, 2014 and December 31, 2013, respectively. Rest of World contains assets from the Republic of Korea, including those assets acquired as a part of our acquisition of Ticket Monster described in Note 2 "Business Combinations," of $395.0 million as of September 30, 2014. There were no other individual countries that represented more than 10% of consolidated total assets as of September 30, 2014 and December 31, 2013, respectively.
Revenue by Segment and Category [Table Text Block]	'
	The following table summarizes the Company's third party and other and direct revenue by category for its three reportable segments for the three months ended September 30, 2014 and 2013 (in thousands):
		North America							EMEA							Rest of World						Consolidated
		Three Months Ended September 30,							Three Months Ended September 30,							Three Months Ended September 30,						Three Months Ended September 30,
		2014			2013				2014			2013				2014			2013			2014			2013
	Local (1):
	Third party and other	$	161,912		$	161,306			$	90,002		$	92,141			$	45,085		$	51,900		$	296,999		$	305,347
	Direct	—			1,040				—			—				—			—			—			1,040
	Total	161,912			162,346				90,002			92,141				45,085			51,900			296,999			306,387
	Goods:
	Third party	1,139			3,999				14,750			32,008				37,814			17,215			53,703			53,222
	Direct	237,816			181,915				108,360			9,271				11,075			7,846			357,251			199,032
	Total	238,955			185,914				123,110			41,279				48,889			25,061			410,954			252,254
	Travel:
	Third party	17,627			12,578				16,960			14,530				14,514			9,310			49,101			36,418
	Total revenue	$	418,494		$	360,838			$	230,072		$	147,950			$	108,488		$	86,271		$	757,054		$	595,059
	-1	Includes revenue from deals with local merchants, from deals with national merchants, and through local events.
	The following table summarizes the Company's third party and other and direct revenue by category for its three reportable segments for the nine months ended September 30, 2014 and 2013 (in thousands):
		North America							EMEA							Rest of World						Consolidated
		Nine Months Ended							Nine Months Ended							Nine Months Ended						Nine Months Ended
		September 30,							September 30,							September 30,						September 30,
		2014			2013				2014			2013				2014			2013			2014			2013
	Local (1):
	Third party and other	$	503,659		$	510,284			$	295,607		$	313,959			$	131,610		$	141,163		$	930,876		$	965,406
	Direct	—			1,733				—			—				—			—			—			1,733
	Total	503,659			512,017				295,607			313,959				131,610			141,163			930,876			967,139
	Goods:
	Third party	3,859			11,794				49,070			110,821				112,686			50,262			165,615			172,877
	Direct	714,157			511,357				296,342			18,903				23,595			20,249			1,034,094			550,509
	Total	718,016			523,151				345,412			129,724				136,281			70,511			1,199,709			723,386
	Travel:
	Third party	51,812			42,406				47,636			48,027				36,234			24,250			135,682			114,683
	Total revenue	$	1,273,487		$	1,077,574			$	688,655		$	491,710			$	304,125		$	235,924		$	2,266,267		$	1,805,208
	-1	Includes revenue from deals with local merchants, from deals with national merchants, and through local events.
Gross Profit by Segment and Category [Table Text Block]	'
	The following table summarizes the Company's gross profit by category for its three reportable segments for the three months ended September 30, 2014 and 2013 (in thousands):
		North America							EMEA							Rest of World						Consolidated
		Three Months Ended							Three Months Ended							Three Months Ended						Three Months Ended
		September 30,							September 30,							September 30,						September 30,
		2014			2013				2014			2013				2014			2013			2014			2013
	Local (1):
	Third party and other	$	138,189		$	139,737			$	83,956		$	81,808			$	38,592		$	44,435		$	260,737		$	265,980
	Direct	—			(847		)		—			—				—			—			—			(847		)
	Total	138,189			138,890				83,956			81,808				38,592			44,435			260,737			265,133
	Goods:
	Third party	951			3,519				12,307			28,036				23,986			11,530			37,244			43,085
	Direct	23,002			18,090				19,945			907				(1,109		)	486			41,838			19,483
	Total	23,953			21,609				32,252			28,943				22,877			12,016			79,082			62,568
	Travel:
	Third party	14,000			11,070				15,440			12,930				10,885			7,921			40,325			31,921
	Total gross profit	$	176,142		$	171,569			$	131,648		$	123,681			$	72,354		$	64,372		$	380,144		$	359,622
	-1	Includes gross profit from deals with local merchants, from deals with national merchants, and through local events.
	The following table summarizes the Company's gross profit by category for its three reportable segments for the nine months ended September 30, 2014 and 2013 (in thousands):
		North America							EMEA							Rest of World						Consolidated
		Nine Months Ended							Nine Months Ended							Nine Months Ended						Nine Months Ended
		September 30,							September 30,							September 30,						September 30,
		2014			2013				2014			2013				2014			2013			2014			2013
	Local (1):
	Third party and other	$	433,485		$	441,787			$	274,395		$	278,515			$	108,958		$	119,810		$	816,838		$	840,112
	Direct	—			(790		)		—			—				—			—			—			(790		)
	Total	433,485			440,997				274,395			278,515				108,958			119,810			816,838			839,322
	Goods:
	Third party	3,239			10,317				43,019			96,264				72,101			27,507			118,359			134,088
	Direct	56,279			50,725				51,967			(239		)		(2,466		)	187			105,780			50,673
	Total	59,518			61,042				94,986			96,025				69,635			27,694			224,139			184,761
	Travel:
	Third party	42,807			36,472				44,003			42,393				27,940			20,377			114,750			99,242
	Total gross profit	$	535,810		$	538,511			$	413,384		$	416,933			$	206,533		$	167,881		$	1,155,727		$	1,123,325
	-1	Includes gross profit from deals with local merchants, from deals with national merchants, and through local events.

Business_Combinations_and_Acqu2

Business Combinations and Acquisitions of Noncontrolling Interests Business Combinations (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2014		Dec. 31, 2013
Business Acquisition [Line Items]	'		'		'
Common stock issued in connection with acquisition of business, shares	'		13,825,283		'
Number of Businesses Acquired	'		4		'
Business Combination, External Transaction Costs	$712		$3,137		'
Purchase Price Allocation [Abstract]	'		'		'
Goodwill	441,290		441,290		220,827
Ticket Monster [Member]	'		'		'
Consideration Transferred [Abstract]	'		'		'
Business Combinations, cash transferred	'		96,496		'
Business Combination, issuance of Class A common stock	'		162,862		'
Business Combination, Consideration Transferred	'		259,358		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Cash and Equivalents	24,768		24,768		'
Business Combination, Current Assets, Receivables	15,832		15,832		'
Business Combination, Current Assets, Deferred Income Taxes	1,264		1,264		'
Business Combination, Current Assets, Prepaid Expense and Other Assets	829		829		'
Business Combination, Property, Plant, and Equipment	5,944		5,944		'
Goodwill	220,592		220,592		'
Business Combination, Other Noncurrent Assets	3,033		3,033		'
Business Combination, Assets	381,356		381,356		'
Business Combination, Current Liabilities, Accounts Payable	5,951		5,951		'
Business Combination, Accrued Merchant and Supplier Payables	82,934		82,934		'
Business Combinations, Accrued Expenses	22,700		22,700		'
Business Combination, Current Liabilities, Other	3,482		3,482		'
Business Combination, Deferred Tax Liabilities Noncurrent	1,264		1,264		'
Business Combination, Noncurrent Liabilities, Other	5,667		5,667		'
Business Combination, Liabilities	121,998		121,998		'
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	259,358		259,358		'
Ticket Monster [Member] | Subscriber Relationships [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	57,022	[1]	57,022	[1]	'
Ticket Monster [Member] | Merchant Relationships [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	32,176	[1]	32,176	[1]	'
Ticket Monster [Member] | Developed Technology [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	571	[1]	571	[1]	'
Ticket Monster [Member] | Trade names [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	19,325	[1]	19,325	[1]	'
Ideeli [Member]	'		'		'
Consideration Transferred [Abstract]	'		'		'
Business Combinations, cash transferred	'		42,339		'
Business Combination, Consideration Transferred, Liabilities Incurred	'		359		'
Business Combination, Consideration Transferred	'		42,698		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Cash and Equivalents	79		79		'
Business Combination, Current Assets, Receivables	988		988		'
Business Combination, Current Assets, Deferred Income Taxes	572		572		'
Business Combination, Current Assets, Prepaid Expense and Other Assets	22,081		22,081		'
Business Combination, Property, Plant, and Equipment	8,173		8,173		'
Goodwill	5,379		5,379		'
Business Combination, Deferred Tax Assets Noncurrent	7,753		7,753		'
Business Combination, Assets	62,115		62,115		'
Business Combination, Current Liabilities, Accounts Payable	1,640		1,640		'
Business Combination, Accrued Merchant and Supplier Payables	4,092		4,092		'
Business Combinations, Accrued Expenses	9,118		9,118		'
Business Combination, Current Liabilities, Other	482		482		'
Business Combination, Deferred Tax Liabilities Noncurrent	332		332		'
Business Combination, Noncurrent Liabilities, Other	3,753		3,753		'
Business Combination, Liabilities	19,417		19,417		'
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	42,698		42,698		'
Ideeli [Member] | Subscriber Relationships [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	5,490	[1]	5,490	[1]	'
Ideeli [Member] | Brand Relationships [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	7,100	[1]	7,100	[1]	'
Ideeli [Member] | Trade names [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	4,500	[1]	4,500	[1]	'
Series of Individually Immaterial Business Acquisitions [Member]	'		'		'
Consideration Transferred [Abstract]	'		'		'
Business Combinations, cash transferred	'		3,477		'
Business Combination, Contingent Consideration	'		4,006		'
Business Combination, Consideration Transferred	'		7,483		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	-52		-52		'
Business Combination, Cash and Equivalents	200		200		'
Goodwill	6,261		6,261		'
Business Combination, Deferred Tax Liabilities Noncurrent	433		433		'
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	7,483		7,483		'
Series of Individually Immaterial Business Acquisitions [Member] | Subscriber Relationships [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	560	[2]	560	[2]	'
Series of Individually Immaterial Business Acquisitions [Member] | Developed Technology [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	568	[2]	568	[2]	'
Series of Individually Immaterial Business Acquisitions [Member] | Brand Relationships [Member]	'		'		'
Purchase Price Allocation [Abstract]	'		'		'
Business Combination, Intangible assets	$579	[2]	$579	[2]	'
Maximum [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'5 years 0 months 0 days		'
Maximum [Member] | Ticket Monster [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'5 years 0 months 0 days		'
Maximum [Member] | Ideeli [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'5 years 0 months 0 days		'
Maximum [Member] | Series of Individually Immaterial Business Acquisitions [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'5 years 0 months 0 days		'
Minimum [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'1 year 0 months 0 days		'
Minimum [Member] | Ticket Monster [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'2 years 0 months 0 days		'
Minimum [Member] | Ideeli [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'3 years 0 months 0 days		'
Minimum [Member] | Series of Individually Immaterial Business Acquisitions [Member]	'		'		'
Business Acquisition [Line Items]	'		'		'
Finite-Lived Intangible Asset, Useful Life	'		'3 years 0 months 0 days		'
[1]	The acquired intangible assets have estimated useful lives of between 2 and 5 years.
[2]	Acquired intangible assets have estimated useful lives of between 3 and 5 years.

Business_Combinations_and_Acqu3

Business Combinations and Acquisitions of Noncontrolling Interests Business Acquisitions, Pro Forma Information (Details) (USD $)	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014
			Ticket Monster [Member]	Ticket Monster [Member]	Ideeli [Member]	Ideeli [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]	'	'	'	'	'	'
Business Acquisition, Pro Forma Revenue	$642,645	$1,949,406	'	'	'	'
Business Acquisition, Pro Forma Net Income (Loss)	-23,004	-79,936	'	'	'	'
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual	'	'	-6,445	-30,263	-450	-3,661
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	'	'	$42,785	$107,373	$20,613	$58,078

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets Goodwill Activity by Segment (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014
Goodwill [Roll Forward]	'
Goodwill, beginning of period	$220,827
Goodwill, related to acquisitions	232,232
Goodwill, other adjustments	-11,769	[1]
Goodwill, end of period	441,290
North America [Member]	'
Goodwill [Roll Forward]	'
Goodwill, beginning of period	85,457
Goodwill, related to acquisitions	11,640
Goodwill, other adjustments	-157	[1]
Goodwill, end of period	96,940
EMEA [Member]	'
Goodwill [Roll Forward]	'
Goodwill, beginning of period	115,669
Goodwill, related to acquisitions	0
Goodwill, other adjustments	-9,578	[1]
Goodwill, end of period	106,091
ROW [Member]	'
Goodwill [Roll Forward]	'
Goodwill, beginning of period	19,701
Goodwill, related to acquisitions	220,592
Goodwill, other adjustments	-2,034	[1]
Goodwill, end of period	$238,259
[1]	(1)Represents the impact of changes in foreign exchange rates on goodwill.

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets Other Intangible Assets (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	$224,019	$101,280
Accumulated Amortization, Intangible Assets	104,209	72,837
Net Carrying Value, Intangible Assets	119,810	28,443
Subscriber Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	105,108	45,541
Accumulated Amortization, Intangible Assets	44,891	30,866
Net Carrying Value, Intangible Assets	60,217	14,675
Merchant Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	40,653	9,186
Accumulated Amortization, Intangible Assets	16,522	7,991
Net Carrying Value, Intangible Assets	24,131	1,195
Trade names [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	29,980	6,739
Accumulated Amortization, Intangible Assets	9,800	6,739
Net Carrying Value, Intangible Assets	20,180	0
Developed Technology [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	23,415	23,038
Accumulated Amortization, Intangible Assets	21,663	19,547
Net Carrying Value, Intangible Assets	1,752	3,491
Brand Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	7,664	'
Accumulated Amortization, Intangible Assets	1,103	'
Net Carrying Value, Intangible Assets	6,561	'
Other Intangible Assets [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value, Intangible Assets	17,199	16,776
Accumulated Amortization, Intangible Assets	10,230	7,694
Net Carrying Value, Intangible Assets	$6,969	$9,082

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets Estimated Future Amortization Expense (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Amortization of Intangible Assets	$11,829	$5,333	$36,068	$16,131
Finite-Lived Intangible Assets, Net, Amortization Expense [Abstract]	'	'	'	'
2014	11,094	'	11,094	'
2015	39,055	'	39,055	'
2016	32,912	'	32,912	'
2017	18,575	'	18,575	'
2018	18,089	'	18,089	'
Thereafter	85	'	85	'
Finite-Lived Intangible Assets, Amortization Expense, Total	$119,810	'	$119,810	'
Minimum [Member]	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Finite-Lived Intangible Asset, Useful Life	'	'	'1 year 0 months 0 days	'
Maximum [Member]	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'
Finite-Lived Intangible Asset, Useful Life	'	'	'5 years 0 months 0 days	'

Investments_Investments_Table_

Investments Investments Table (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Cost method investments	$15,920	$15,788
Equity method investments	1,231	1,690
Total cost and equity method investments	17,151	17,478
Available-for-sale securities	6,488	3,174
Available-for-Sale Securities, Ownership Percentage	'	19.00%
Total investments	23,639	20,652
Payments to Acquire Available-for-sale Securities	4,599	'
Convertible debt securities [Member]	'	'
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Available-for-sale securities	2,030	3,174
Redeemable preferred shares [Member]	'	'
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Available-for-sale securities	$4,458	$0
Maximum [Member]	'	'
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Equity Method Investments, Ownership Percentage	50.00%	50.00%
Available-for-Sale Securities, Ownership Percentage	23.00%	'
Maximum [Member] | Cost-method Investments [Member]	'	'
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Cost Method Investments, Ownership Percentage	19.00%	19.00%
Minimum [Member]	'	'
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Equity Method Investments, Ownership Percentage	21.00%	21.00%
Available-for-Sale Securities, Ownership Percentage	19.00%	'
Minimum [Member] | Cost-method Investments [Member]	'	'
Schedule of Cost and Equity Method Investments [Line Items]	'	'
Cost Method Investments, Ownership Percentage	6.00%	6.00%

Investments_Availableforsale_S

Investments Available-for-sale Securities (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Available-for-sale Securities, Amortized Cost Basis	$6,629	$3,370
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax	-141	-196
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	6,488	3,174
Convertible debt securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Available-for-sale Securities, Amortized Cost Basis	2,030	3,370
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax	0	-196
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	2,030	3,174
Redeemable preferred shares [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Available-for-sale Securities, Amortized Cost Basis	4,599	0
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax	-141	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	$4,458	$0

Investments_OtherThanTemporary

Investments Other-Than-Temporary-Impairment (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Other-Than-Temporary-Impairment [Abstract]	'	'	'	'
Other-than-temporary impairment of available-for-sale security	$1,340	$0	$1,340	$0

Supplemental_Consolidated_Bala2

Supplemental Consolidated Balance Sheet and Statement of Operations Information (Details) (USD $)	3 Months Ended			9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Interest and Other Income [Abstract]	'		'	'		'	'
Interest income	$409		$487	$1,151		$1,348	'
Interest Expense	-277		-39	-444		-187	'
Impairment of investment	-1,448		0	-2,036		0	'
Loss on equity method investments	-91		-25	-459		-58	'
Foreign exchange (losses) gains, net	-18,638		326	-20,108		-11,156	'
Other	22		83	10		223	'
Other expense, net	-20,023		832	-21,886		-9,830	'
Prepaid Expense and Other Assets, Current [Abstract]	'		'	'		'	'
Current portion of unamortized tax effects on intercompany transactions	23,377		'	23,377		'	28,502
Finished goods inventories	57,301		'	57,301		'	57,097
Prepaid expenses	42,603		'	42,603		'	29,404
Restricted cash	11,056		'	11,056		'	14,579
VAT and income taxes receivable	82,804		'	82,804		'	52,960
Prepaid marketing	9,832		'	9,832		'	17,301
Other	16,777		'	16,777		'	10,572
Total prepaid expenses and other current assets	243,750		'	243,750		'	210,415
Merchant and Supplier Payables [Abstract]	'		'	'		'	'
Accrued merchant payables	575,145		'	575,145		'	518,233
Accrued supplier payables	179,483	[1]	'	179,483	[1]	'	234,710	[1]
Total accrued merchant and supplier payables	754,628		'	754,628		'	752,943
Accrued Expenses [Abstract]	'		'	'		'	'
Marketing	11,860		'	11,860		'	12,001
Refunds reserve	29,221		'	29,221		'	38,597
Payroll and benefits	64,751		'	64,751		'	64,966
Customer credits	46,297		'	46,297		'	44,728
Professional fees	16,902		'	16,902		'	18,906
Other	54,646		'	54,646		'	47,788
Total accrued expenses	223,677		'	223,677		'	226,986
Current liabilities [Abstract]:	'		'	'		'	'
Income taxes payable	27,020		'	27,020		'	21,994
VAT payable	30,476		'	30,476		'	37,627
Sales taxes payable	6,229		'	6,229		'	10,412
Deferred revenue	50,677		'	50,677		'	47,259
Other	19,714		'	19,714		'	15,426
Total other current liabilities	134,116		'	134,116		'	132,718
Liabilities, Noncurrent [Abstract]	'		'	'		'	'
Long-term tax liabilities	108,233		'	108,233		'	109,286
Deferred rent	13,216		'	13,216		'	9,148
Other	30,037		'	30,037		'	13,263
Total other non-current liabilities	151,486		'	151,486		'	131,697
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'		'	'		'	'
Foreign currency translation adjustments, beginning of period	'		'	24,952		'	'
Unrealized loss on available-for-sale securities, net of tax, beginning of period	'		'	-122		'	'
Accumulated other comprehensive income, beginning of period	'		'	24,830		'	'
Other comprehensive income (loss) before reclassification adjustments	'		'	9,287		'	'
Reclassification adjustment for impairment included in net loss	'		0	831		0	'
Foreign currency translation adjustments	1,827		-1,072	9,899		11,416	'
Other comprehensive income	2,233		-1,181	9,931		11,397	'
Foreign currency translation adjustments, end of period	35,038		'	35,038		'	'
Unrealized loss on available-for-sale securities, net of tax, end of period	-90		'	-90		'	'
Accumulated other comprehensive income, end of period	34,948		'	34,948		'	'
Other-than-temporary impairment of available-for-sale security	1,340		0	1,340		0	'
Tax effect	-509		0	-509		0	'
Accumulated Translation Adjustment [Member]	'		'	'		'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'		'	'		'	'
Other comprehensive income (loss) before reclassification adjustments	'		'	10,086		'	'
Reclassification adjustment for impairment included in net loss	'		'	0		'	'
Foreign currency translation adjustments	'		'	10,086		'	'
Accumulated Net Unrealized Investment Gain (Loss) [Member]	'		'	'		'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'		'	'		'	'
Other comprehensive income (loss) before reclassification adjustments	'		'	-799		'	'
Reclassification adjustment for impairment included in net loss	'		'	831		'	'
Unrealized loss on available-for-sale debt security, net of tax	'		'	32		'	'
Parent [Member]	'		'	'		'	'
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'		'	'		'	'
Foreign currency translation adjustments	'		'	10,086		'	'
Unrealized loss on available-for-sale debt security, net of tax	'		'	32		'	'
Other comprehensive income	'		'	$10,118		'	'
[1]	(1)Amounts include payables to suppliers of inventories and providers of shipping and fulfillment services.

Commitments_and_Contingencies_1

Commitments and Contingencies Operating Leases (Details) (USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'
2014	$1,348
2015	5,148
2016	4,936
2017	4,342
2018	2,631
Thereafter	11,110
Total minimum lease payments	$29,515

Commitments_and_Contingencies_2

Commitments and Contingencies Legal Matters (Details) (USD $)	3 Months Ended	9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2011	Sep. 30, 2014
COMMITMENTS AND CONTINGENCIES [Abstract]	'	'
Restatement of Prior Year Revenue	$14,300	'
Restatement of Prior Year Operating Income	30,000	'
Restatement of Prior Year Income, Net of Tax	22,600	'
Impact of Restatement on Earnings Per Share, Basic	$0.04	'
Litigation Settlement, Expense	'	$8,500

Revolving_Credit_Agreement_Det

Revolving Credit Agreement (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014
Line of Credit Facility [Line Items]	'
Line of Credit Facility, Maximum Borrowing Capacity	250,000
Unrestricted cash covenant	400,000
Line of Credit Facility, Cash Institution Covenant	200,000
Line of Credit [Member]	'
Line of Credit Facility [Line Items]	'
Line of Credit Facility, Maximum Borrowing Capacity	45,000
Minimum [Member]	'
Line of Credit Facility [Line Items]	'
Line of Credit Facility, Interest Rate Description	'0.0025
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Maximum [Member]	'
Line of Credit Facility [Line Items]	'
Line of Credit Facility, Interest Rate Description	'0.02
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.35%

Stockholders_Equity_and_StockB2

Stockholders' Equity and Stock-Based Compensation Initial Public Offering, Convertible Preferred Stock and Common Stock (Details)	12 Months Ended
	Dec. 31, 2012
	NumberofClasses
Classes of common stock, number	3

Stockholders_Equity_and_StockB3

Stockholders' Equity and Stock-Based Compensation Repurchase Program (Details) (USD $)	3 Months Ended	9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013
Employee Stock Purchase Plan [Line Items]	'	'	'
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$109,644	$109,644	'
Common Class A [Member]	'	'	'
Employee Stock Purchase Plan [Line Items]	'	'	'
Stock Repurchase Program, Authorized Amount	'	'	300,000
Stock Repurchased During Period, Shares	1,349,712	21,654,204	'
Stock Repurchased During Period, Value	$8,309	$143,768	'

Stockholders_Equity_and_StockB4

Stockholders' Equity and Stock-Based Compensation Groupon, Inc. Stock Plans (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Share-based Compensation, Number of Shares Available for Grant	45,500,684	'	45,500,684	'
Stock-based compensation	$34,574	$26,870	$89,958	$89,223
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	2,786	2,200	7,905	6,900
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$230,100	'	$230,100	'
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	'	'	'1 year 4 months 10 days	'

Stockholders_Equity_and_StockB5

Stockholders' Equity and Stock-Based Compensation Employee Stock Purchase Plan (Details)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Employee Stock Purchase Plan, shares authorized	10,000,000	'
Employee Stock Purchase Plan, issued shares	857,171	774,288

Stockholders_Equity_and_StockB6

Stockholders' Equity and Stock-Based Compensation Stock Option Activity (Details) (Stock Options [Member], USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Stock Options [Member]	'	'
Options [Abstract]	'	'
Options, Outstanding, Number	3,355,054	'
Exercise of stock options, shares	-805,225	'
Options, Forfeited Shares	-59,489	'
Options, Outstanding, Number	2,490,340	3,355,054
Options, Exercisable, Number	2,484,486	'
Weighted-Average Exercise Price [Abstract]	'	'
Options, Outstanding, Weighted Average Exercise Price	$1.11	'
Options, Exercises in Period, Weighted Average Exercise Price	$1	'
Options, Forfeitures in Period, Weighted Average Exercise Price	$2.41	'
Options, Outstanding, Weighted Average Exercise Price	$1.14	$1.11
Options, Weighted Average Exercise Price	$1.13	'
Weighted Average Remaining Contractual Term [Abstract]	'	'
Options, Outstanding, Weighted Average Remaining Contractual Term	'5 years 2 months 50 days	'6 years 0 months 15 days
Options, Outstanding, Weighted Average Remaining Contractual Term	'5 years 2 months 50 days	'6 years 0 months 15 days
Options, Exercisable, Weighted Average Remaining Contractual Term	'5 years 2 months 50 days	'
Aggregate Intrinsic Value [Abstract]	'	'
Options, Outstanding, Intrinsic Value	$35,742	'
Options, Outstanding, Intrinsic Value	13,796	35,742
Options, Exercisable, Intrinsic Value	$13,789	'

Stockholders_Equity_and_StockB7

Stockholders' Equity and Stock-Based Compensation Restricted Stock Unit Activity (Details) (Restricted Stock Units (RSUs) [Member], USD $)	9 Months Ended
	Sep. 30, 2014
Restricted Stock Units (RSUs) [Member]	'
Restricted Stock Units [Abstract]	'
Equity Instruments Other than Options, Nonvested, Number	41,648,055
Equity Instruments Other than Options, Grants in Period	22,885,522
Equity Instruments Other than Options, Vested in Period	-12,741,462
Equity Instruments Other than Options, Forfeited in Period	-9,586,804
Equity Instruments Other than Options, Nonvested, Number	42,205,311
Weighted Average Grant Date Fair Value [Abstract]	'
Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$8.06
Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$7.83
Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$7.97
Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$8
Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$8.03

Stockholders_Equity_and_StockB8

Stockholders' Equity and Stock-Based Compensation Performance Share Unit Activity (Details) (Performance Shares [Member], USD $)	9 Months Ended
	Sep. 30, 2014
Performance Shares [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Performance Share Units, Shares Granted	2,000,000
Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$8.07

Stockholders_Equity_and_StockB9

Stockholders' Equity and Stock-Based Compensation Restricted Stock, Acquired (Details) (Restricted Stock [Member], USD $)	9 Months Ended
	Sep. 30, 2014
Restricted Stock [Member]	'
Restricted Stock [Abstract]	'
Equity Instruments Other than Options, Nonvested, Number	97,677
Equity Instruments Other than Options, Vested in Period	-48,890
Equity Instruments Other than Options, Forfeited in Period	-13,129
Equity Instruments Other than Options, Nonvested, Number	35,658
Weighted Average Grant Date Fair Value [Abstract]	'
Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$14
Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$14.45
Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$17.07
Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$15.59

Income_Taxes_Text_Details

Income Taxes Text (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
(Benefit) provision for income taxes	($6,434)	$15,936	$20,181	$62,657	'
(Loss) income before (benefit) provision for income taxes	-25,452	14,644	-55,122	52,572	'
Effective Tax Rate, Percent	25.30%	108.80%	-36.60%	119.20%	'
Federal Statutory Income Tax Rate, Percent	'	'	35.00%	'	'
Income Tax Examination, Increase (Decrease) in Liability from Prior Year	-7,700	'	-7,700	'	'
Potential Change in Unrecognized Tax Benefits	35,500	'	35,500	'	'
Prepaid Taxes	23,377	'	23,377	'	28,502
Prepaid Expenses and Other Current Assets [Member]	'	'	'	'	'
Prepaid Taxes	23,400	'	23,400	'	28,500
Other Assets [Member]	'	'	'	'	'
Prepaid Taxes	1,500	'	1,500	'	20,400
Future amortization through 2014 [Member]	'	'	'	'	'
Prepaid Taxes	6,200	'	6,200	'	'
Future amortization through 2015 [Member]	'	'	'	'	'
Prepaid Taxes	$18,700	'	$18,700	'	'

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value, Assets and Liabilities Measured at Fair Value (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	$6,488	$3,174
Fair Value, Measurements, Recurring [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	440,578	585,514
Contingent Consideration, Fair Value Disclosure	2,986	606
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	440,578	585,514
Contingent Consideration, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Contingent Consideration, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Contingent Consideration, Fair Value Disclosure	2,986	606
Convertible debt securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	2,030	3,174
Convertible debt securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	0	0
Convertible debt securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	0	0
Convertible debt securities [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	2,030	3,174
Redeemable preferred shares [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	4,458	0
Redeemable preferred shares [Member] | Fair Value, Measurements, Recurring [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	0	0
Redeemable preferred shares [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	0	0
Redeemable preferred shares [Member] | Fair Value, Measurements, Recurring [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale securities	$4,458	$0

Fair_Value_Measurements_Fair_V1

Fair Value Measurements Fair Value, Reconciliation of Level 3 - Assets (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Available-for-sale Securities	($1,340)		$0		($1,340)		$0
Convertible Debt Securities [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
AFS Securities, Beginning Asset Value	2,630		3,233		3,174		3,087
AFS Debt Security, (losses) included in OCI	740		-177		196		-31
AFS Securities, Ending Asset Value	2,030		3,056		2,030		3,056
Unrealized Gains (Losses) Still Held - Assets	-600	[1]	-177	[1]	-1,144	[1]	-31	[1]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Available-for-sale Securities	-1,340		0		-1,340		0
Redeemable preferred shares [Member]	'		'		'		'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
AFS Securities, Beginning Asset Value	4,544	[2]	42,539	[2]	0	[2]	42,539	[2]
AFS Debt Security, (losses) included in OCI	-86		0		-141		0
Purchase of redeemable preferred shares	0		0		4,599		0
AFS Securities, Ending Asset Value	4,458	[2]	42,539	[2]	4,458	[2]	42,539	[2]
Unrealized Gains (Losses) Still Held - Assets	($86)	[1]	'		($141)	[1]	$0	[1]
[1]	Represents the unrealized losses or gains recorded in earnings and/or other comprehensive (loss) income during the period for assets and liabilities classified as Level 3 that are still held (or outstanding) at the end of the period.
[2]	For the three and nine months ended SeptemberB 30, 2013, the Company's investments in Life Media Limited (F-tuan) preferred shares were previously classified as cost method investments and have been reclassified to the available-for-sale category in this table. The balance as of SeptemberB 30, 2013 represents the Companybs investments in F-tuan preferred shares, which were written down to zero through an other-than-temporary impairment charge as of December 31, 2013 and continue to have an estimated fair value of zero as of SeptemberB 30, 2014. The $4.5 million balance as of SeptemberB 30, 2014 represents the Company's investment in the preferred shares of an online home services company during the three months ended March 31, 2014, as described in Note 4 "Investments."

Fair_Value_Measurements_Fair_V2

Fair Value Measurements Fair Value, Reconciliation of Level 3 - Liabilities (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'		'		'		'
Business Combination, Contingent Consideration Arrangements, Change in Range of Outcomes, Contingent Consideration, Liability, Value, High	'		'		$7,331		'
Contingent Consideration, Beginning Value	4,006		6,854		606		7,601
Contingent Consideration, Issuances	0		3,537		4,006		3,567
Contingent Consideration, Settlements	0		-750		-424		-780
Contingent Consideration, Reclass	0		0		-143		0
(Gain) loss, net from changes in fair value of contingent consideration	-1,020	[1]	-1,529	[1]	-1,059		-2,276
Contingent Consideration, Ending Value	2,986		8,112		2,986		8,112
Contingent Consideration, Unrealized Gain Loss	($1,020)	[2]	($1,408)	[2]	($1,020)	[2]	($2,155)	[2]
[1]	Changes in the fair value of contingent consideration liabilities are classified within "Acquisition-related (benefit) expense, net" on the condensed consolidated statements of operations.
[2]	Represents the unrealized losses or gains recorded in earnings and/or other comprehensive (loss) income during the period for assets and liabilities classified as Level 3 that are still held (or outstanding) at the end of the period.

Fair_Value_Measurements_Financ

Fair Value Measurements Financial Assets and Liabilities, Not Measured at Fair Value (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cost method investments	$15,920	$15,788
Cost Method Investments, Fair Value Disclosure	$16,037	$15,573

Loss_Per_Share_of_Class_A_and_2

Loss Per Share of Class A and Class B Common Stock Basic and Diluted Earnings Per Share, 2013, 2012 and 2011 (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Earnings Per Share, Basic [Abstract]	'		'		'		'
Net loss	($19,018,000)		($1,292,000)		($75,303,000)		($10,085,000)
Net income attributable to noncontrolling interests	2,190,000		1,288,000		6,575,000		4,061,000
Basic, weighted average number of shares outstanding	669,526,524		666,432,848		675,814,535		662,531,567
Basic, net (loss) earnings per share	($0.03)		$0		($0.12)		($0.02)
Earnings Per Share, Diluted [Abstract]	'		'		'		'
Basic, weighted average number of shares outstanding	669,526,524		666,432,848		675,814,535		662,531,567
Diluted, weighted average number of shares outstanding	669,526,524		666,432,848		675,814,535		662,531,567
Diluted, net (loss) earnings per share	($0.03)		$0		($0.12)		($0.02)
Common Class A [Member]	'		'		'		'
Earnings Per Share, Basic [Abstract]	'		'		'		'
Net loss	-18,950,000		-1,287,000		-75,035,000		-10,049,000
Net income attributable to noncontrolling interests	2,182,000		1,283,000		6,552,000		4,046,000
Net (loss) income attributable to common stockholders	-21,132,000		-2,570,000		-81,587,000		-14,095,000
Basic, weighted average number of shares outstanding	667,126,548		664,032,872		673,414,559		660,131,591
Basic, net (loss) earnings per share	($0.03)		$0		($0.12)		($0.02)
Earnings Per Share, Diluted [Abstract]	'		'		'		'
Net Income (Loss) Available to Common Stockholders, Diluted	-21,132,000		-2,570,000		-81,587,000		-14,095,000
Reallocation of net income attributable to common stockholders as a result of conversion of Class B	0	[1]	0	[1]	0	[1]	0	[1]
Allocation of net income attributable to common stockholders	-21,132,000		-2,570,000		-81,587,000		-14,095,000
Basic, weighted average number of shares outstanding	667,126,548		664,032,872		673,414,559		660,131,591
Conversion of Class B	0	[1]	0	[1]	0	[1]	0	[1]
Employee stock options	0	[1]	0	[1]	0	[1]	0	[1]
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units	0	[1]	0	[1]	0	[1]	0	[1]
Diluted, weighted average number of shares outstanding	667,126,548	[1]	664,032,872	[1]	673,414,559	[1]	660,131,591	[1]
Diluted, net (loss) earnings per share	($0.03)		$0		($0.12)		($0.02)
Common Class B [Member]	'		'		'		'
Earnings Per Share, Basic [Abstract]	'		'		'		'
Net loss	-68,000		-5,000		-268,000		-36,000
Net income attributable to noncontrolling interests	8,000		5,000		23,000		15,000
Net (loss) income attributable to common stockholders	-76,000		-10,000		-291,000		-51,000
Basic, weighted average number of shares outstanding	2,399,976		2,399,976		2,399,976		2,399,976
Basic, net (loss) earnings per share	($0.03)		$0		($0.12)		($0.02)
Earnings Per Share, Diluted [Abstract]	'		'		'		'
Net Income (Loss) Available to Common Stockholders, Diluted	-76,000		-10,000		-291,000		-51,000
Reallocation of net income attributable to common stockholders as a result of conversion of Class B	0	[1]	0	[1]	0	[1]	0	[1]
Allocation of net income attributable to common stockholders	-76,000		-10,000		-291,000		-51,000
Basic, weighted average number of shares outstanding	2,399,976		2,399,976		2,399,976		2,399,976
Conversion of Class B	0	[1]	0	[1]	0	[1]	0	[1]
Employee stock options	0	[1]	0	[1]	0	[1]	0	[1]
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units	$0	[1]	$0	[1]	$0	[1]	$0	[1]
Diluted, weighted average number of shares outstanding	2,399,976	[1]	2,399,976	[1]	2,399,976	[1]	2,399,976	[1]
Diluted, net (loss) earnings per share	($0.03)		$0		($0.12)		($0.02)
[1]	Conversion of Class B shares into Class A shares and outstanding equity awards have not been reflected in the diluted loss per share calculation for the three and nine months ended SeptemberB 30, 2014 and 2013 because the effect would be antidilutive.

Loss_Per_Share_of_Class_A_and_3

Loss Per Share of Class A and Class B Common Stock Schedule of Equity Antidilutive Securities (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive Securities, Amount	47,103,519	48,595,273	46,206,071	46,160,376
Performance share units	'	'	2,000,000	'
Stock Options [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive Securities, Amount	2,610,764	5,023,559	2,905,390	6,242,363
Restricted Stock Units (RSUs) [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive Securities, Amount	43,989,496	43,020,496	42,713,167	39,076,490
Restricted Stock [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive Securities, Amount	36,988	217,005	58,718	357,339
Employee Stock [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive Securities, Amount	466,271	334,213	528,796	484,184

Segment_Information_Details

Segment Information (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Segment Reporting Information [Line Items]	'		'		'		'
Number of Reportable Segments	'		'		3		'
Total revenue	$757,054		$595,059		$2,266,267		$1,805,208
Costs and Expenses	728,213	[1]	555,906	[1]	2,207,467	[1]	1,655,859	[1]
Segment operating income (loss)	28,841	[1]	39,153	[1]	58,800	[1]	149,349	[1]
Stock-based compensation	34,574		26,870		89,958		89,223
Acquisition-related (benefit) expense, net	-304		-1,529		2,078		-2,276
(Loss) income from operations	-5,429		13,812		-33,236		62,402
Other (expense) income, net	-20,023		832		-21,886		-9,830
(Loss) income before (benefit) provision for income taxes	-25,452		14,644		-55,122		52,572
(Benefit) provision for income taxes	-6,434		15,936		20,181		62,657
Net loss	-19,018		-1,292		-75,303		-10,085
UNITED STATES	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Total revenue	409,300		349,100		1,242,400		1,039,700
SWITZERLAND	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Total revenue	117,700		'		312,000		'
North America [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Total revenue	418,494	[2]	360,838	[2]	1,273,487	[2]	1,077,574	[2]
Costs and Expenses	405,910	[1]	335,670	[1]	1,234,973	[1]	962,532	[1]
Segment operating income (loss)	12,584	[1]	25,168	[1]	38,514	[1]	115,042	[1]
Stock-based compensation	28,493		21,082		74,179		69,494
Acquisition-related (benefit) expense, net	-304		-984		1,934		-1,364
EMEA [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Total revenue	230,072		147,950		688,655		491,710
Costs and Expenses	207,643	[1]	132,346	[1]	619,594	[1]	417,222	[1]
Segment operating income (loss)	22,429	[1]	15,604	[1]	69,061	[1]	74,488	[1]
Stock-based compensation	2,687		2,616		7,187		9,082
Acquisition-related (benefit) expense, net	0		-545		144		-912
ROW [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Total revenue	108,488		86,271		304,125		235,924
Costs and Expenses	114,660	[1]	87,890	[1]	352,900	[1]	276,105	[1]
Segment operating income (loss)	-6,172	[1]	-1,619	[1]	-48,775	[1]	-40,181	[1]
Stock-based compensation	3,394		3,172		8,592		10,647
Acquisition-related (benefit) expense, net	$0		$0		$0		$0
[1]	Segment cost of revenue and operating expenses and segment operating income (loss) exclude stock-based compensation and acquisition-related (benefit) expense, net. This presentation corresponds to the measure of segment profit or loss that the Company's chief operating decision-maker uses in assessing segment performance and making resource allocation decisions. The following table summarizes the Company's stock-based compensation expense and acquisition-related (benefit) expense, net by reportable segment for the three and nine months ended SeptemberB 30, 2014 and 2013 (in thousands): Three Months Ended September 30,B Nine Months Ended September 30, 2014B 2013B 2014B 2013 Stock-based compensationB Acquisition-relatedB Stock-based compensationB Acquisition-relatedB Stock-based compensationB Acquisition-relatedB Stock-based compensationB Acquisition-relatedNorth AmericaB $28,493B $(304)B $21,082B $(984)B $74,179B $1,934B $69,494B $(1,364)EMEAB 2,687B bB 2,616B (545)B 7,187B 144B 9,082B (912)Rest of WorldB 3,394B bB 3,172B bB 8,592B bB 10,647B bConsolidatedB $34,574B $(304)B $26,870B $(1,529)B $89,958B $2,078B $89,223B $(2,276)Acquisition-related (benefit) expense, net for the North America segment includes external transaction costs and gains and losses relating to contingent consideration obligations incurred by U.S. legal entities relating to purchases of businesses that became part of the EMEA and Rest of World segments, which is consistent with the attribution used for internal reporting purposes.
[2]	North America includes revenue from the United States of $409.3 million and $349.1 million for the three months ended September 30, 2014 and 2013, respectively, and $1,242.4 million and $1,039.7 million for the nine months ended September 30, 2014 and 2013, respectively. Beginning in September 2013, direct revenue transactions in the EMEA Goods category have been transacted through a Switzerland-based subsidiary. As a result, EMEA includes revenue from Switzerland of $117.7 million and $312.0 million for the three and nine months ended September 30, 2014, respectively.

Segment_Information_Total_Asse

Segment Information Total Assets (Details) (USD $)

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

In Thousands, unless otherwise specified

UNITED STATES

UNITED STATES

North America [Member]

North America [Member]

EMEA [Member]

EMEA [Member]

ROW [Member]

ROW [Member]

Korea [Member]

Assets, Total [Member]

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Total Assets

$2,072,165

$2,042,010

$940,800

$1,231,300

$978,814

[1]

$1,267,158

[1]

$543,257

$616,126

$550,094

[1]

$158,726

[1]

$395,000

'

Concentration of risk, percentage

'

'

'

'

'

'

'

'

'

'

'

10.00%

[1]

(1)North America contains assets from the United States of $940.8 million and $1,231.3 million as of September 30, 2014 and DecemberB 31, 2013, respectively. Rest of World contains assets from the Republic of Korea, including those assets acquired as a part of our acquisition of Ticket Monster described in Note 2 "Business Combinations," of $395.0 million as of September 30, 2014. There were no other individual countries that represented more than 10% of consolidated total assets as of September 30, 2014 and December 31, 2013, respectively.

Segment_Information_Revenue_by

Segment Information Revenue by Segment and Category (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Primary Categories	'		'		3		'
Third party and other	$399,803		$394,987		$1,232,173		$1,252,966
Direct	357,251		200,072		1,034,094		552,242
Total revenue	757,054		595,059		2,266,267		1,805,208
North America [Member]	'		'		'		'
Total revenue	418,494	[1]	360,838	[1]	1,273,487	[1]	1,077,574	[1]
EMEA [Member]	'		'		'		'
Total revenue	230,072		147,950		688,655		491,710
ROW [Member]	'		'		'		'
Total revenue	108,488		86,271		304,125		235,924
Local [Member]	'		'		'		'
Third party and other	296,999	[2]	305,347	[2]	930,876	[2]	965,406	[2]
Direct	0	[2]	1,040	[2]	0	[2]	1,733	[2]
Total revenue	296,999	[2]	306,387	[2]	930,876	[2]	967,139	[2]
Local [Member] | North America [Member]	'		'		'		'
Third party and other	161,912	[2]	161,306	[2]	503,659	[2]	510,284	[2]
Direct	0	[2]	1,040	[2]	0	[2]	1,733	[2]
Total revenue	161,912	[2]	162,346	[2]	503,659	[2]	512,017	[2]
Local [Member] | EMEA [Member]	'		'		'		'
Third party and other	90,002	[2]	92,141	[2]	295,607	[2]	313,959	[2]
Direct	0	[2]	0	[2]	0	[2]	0	[2]
Total revenue	90,002	[2]	92,141	[2]	295,607	[2]	313,959	[2]
Local [Member] | ROW [Member]	'		'		'		'
Third party and other	45,085	[2]	51,900	[2]	131,610	[2]	141,163	[2]
Direct	0	[2]	0	[2]	0	[2]	0	[2]
Total revenue	45,085	[2]	51,900	[2]	131,610	[2]	141,163	[2]
Goods [Member]	'		'		'		'
Third party and other	53,703		53,222		165,615		172,877
Direct	357,251		199,032		1,034,094		550,509
Total revenue	410,954		252,254		1,199,709		723,386
Goods [Member] | North America [Member]	'		'		'		'
Third party and other	1,139		3,999		3,859		11,794
Direct	237,816		181,915		714,157		511,357
Total revenue	238,955		185,914		718,016		523,151
Goods [Member] | EMEA [Member]	'		'		'		'
Third party and other	14,750		32,008		49,070		110,821
Direct	108,360		9,271		296,342		18,903
Total revenue	123,110		41,279		345,412		129,724
Goods [Member] | ROW [Member]	'		'		'		'
Third party and other	37,814		17,215		112,686		50,262
Direct	11,075		7,846		23,595		20,249
Total revenue	48,889		25,061		136,281		70,511
Travel [Member]	'		'		'		'
Third party and other	49,101		36,418		135,682		114,683
Travel [Member] | North America [Member]	'		'		'		'
Third party and other	17,627		12,578		51,812		42,406
Travel [Member] | EMEA [Member]	'		'		'		'
Third party and other	16,960		14,530		47,636		48,027
Travel [Member] | ROW [Member]	'		'		'		'
Third party and other	$14,514		$9,310		$36,234		$24,250
[1]	North America includes revenue from the United States of $409.3 million and $349.1 million for the three months ended September 30, 2014 and 2013, respectively, and $1,242.4 million and $1,039.7 million for the nine months ended September 30, 2014 and 2013, respectively. Beginning in September 2013, direct revenue transactions in the EMEA Goods category have been transacted through a Switzerland-based subsidiary. As a result, EMEA includes revenue from Switzerland of $117.7 million and $312.0 million for the three and nine months ended September 30, 2014, respectively.
[2]	Includes revenue from deals with local merchants, from deals with national merchants, and through local events.

Segment_Information_Gross_Prof

Segment Information Gross Profit by Segment and Category (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	$380,144		$359,622		$1,155,727		$1,123,325
North America [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	176,142		171,569		535,810		538,511
EMEA [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	131,648		123,681		413,384		416,933
ROW [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	72,354		64,372		206,533		167,881
Local [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	260,737	[1]	265,133	[1]	816,838	[1]	839,322	[1]
Local [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	260,737	[1]	265,980	[1]	816,838	[1]	840,112	[1]
Local [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	0	[1]	-847	[1]	0	[1]	-790	[1]
Local [Member] | North America [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	138,189	[1]	138,890	[1]	433,485	[1]	440,997	[1]
Local [Member] | North America [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	138,189	[1]	139,737	[1]	433,485	[1]	441,787	[1]
Local [Member] | North America [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	0	[1]	-847	[1]	0	[1]	-790	[1]
Local [Member] | EMEA [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	83,956	[1]	81,808	[1]	274,395	[1]	278,515	[1]
Local [Member] | EMEA [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	83,956	[1]	81,808	[1]	274,395	[1]	278,515	[1]
Local [Member] | EMEA [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	0	[1]	0	[1]	0	[1]	0	[1]
Local [Member] | ROW [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	38,592	[1]	44,435	[1]	108,958	[1]	119,810	[1]
Local [Member] | ROW [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	38,592	[1]	44,435	[1]	108,958	[1]	119,810	[1]
Local [Member] | ROW [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	0	[1]	0	[1]	0	[1]	0	[1]
Goods [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	79,082		62,568		224,139		184,761
Goods [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	37,244		43,085		118,359		134,088
Goods [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	41,838		19,483		105,780		50,673
Goods [Member] | North America [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	23,953		21,609		59,518		61,042
Goods [Member] | North America [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	951		3,519		3,239		10,317
Goods [Member] | North America [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	23,002		18,090		56,279		50,725
Goods [Member] | EMEA [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	32,252		28,943		94,986		96,025
Goods [Member] | EMEA [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	12,307		28,036		43,019		96,264
Goods [Member] | EMEA [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	19,945		907		51,967		-239
Goods [Member] | ROW [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	22,877		12,016		69,635		27,694
Goods [Member] | ROW [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	23,986		11,530		72,101		27,507
Goods [Member] | ROW [Member] | Direct [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	-1,109		486		-2,466		187
Travel [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	40,325		31,921		114,750		99,242
Travel [Member] | North America [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	14,000		11,070		42,807		36,472
Travel [Member] | EMEA [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	15,440		12,930		44,003		42,393
Travel [Member] | ROW [Member] | Third party and other [Member]	'		'		'		'
Gross Profit by Category [Line Items]	'		'		'		'
Gross profit	$10,885		$7,921		$27,940		$20,377
[1]	Includes gross profit from deals with local merchants, from deals with national merchants, and through local events.