Twitter (TWTR) 10-Q 8 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 30, 2014
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'TWTR	'
Entity Registrant Name	'TWITTER, INC.	'
Entity Central Index Key	'0001418091	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Non-accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	589,938,826

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$960,755	$841,010
Short-term investments	1,215,840	1,393,044
Accounts receivable, net of allowance for doubtful accounts of $2,633 and $2,020 as of March 31, 2014 and December 31, 2013, respectively	237,860	247,328
Prepaid expenses and other current assets	90,925	93,297
Total current assets	2,505,380	2,574,679
Property and equipment, net	383,272	332,662
Intangible assets	71,451	77,627
Goodwill	363,477	363,477
Other assets	32,629	17,795
Total assets	3,356,209	3,366,240
Current liabilities:	'	'
Accounts payable	19,714	27,994
Accrued and other current liabilities	151,284	110,310
Capital leases, short-term	90,253	87,126
Total current liabilities	261,251	225,430
Capital leases, long-term	102,534	110,520
Deferred and other long-term tax liabilities, net	29,574	59,500
Other long-term liabilities	26,004	20,784
Total liabilities	419,363	416,234
Commitments and contingencies (Note 10)	'	'
Stockholders' equity:	'	'
Common stock, $0.000005 par value-- 5,000,000 shares authorized; 589,298 and 569,922 shares issued and outstanding as of March 31, 2014 and December 31, 2013, respectively	3	3
Additional paid-in capital	4,064,127	3,944,952
Accumulated other comprehensive loss	-296	-323
Accumulated deficit	-1,126,988	-994,626
Total stockholders' equity	2,936,846	2,950,006
Total liabilities and stockholders' equity	$3,356,209	$3,366,240

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, except Per Share data, unless otherwise specified
Allowance for doubtful accounts receivable	$2,633	$2,020
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	5,000,000	5,000,000
Common stock, shares issued	589,298	569,922
Common stock, shares outstanding	589,298	569,922

CONSOLIDATED_STATEMENTS_OF_OPE

CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenue	$250,492	$114,343
Costs and expenses	'	'
Cost of revenue	85,503	41,255
Research and development	149,391	47,574
Sales and marketing	106,235	32,439
General and administrative	38,734	16,982
Total costs and expenses	379,863	138,250
Loss from operations	-129,371	-23,907
Interest income (expense), net	-2,567	-1,233
Other income (expense), net	798	-1,529
Loss before income taxes	-131,140	-26,669
Provision for income taxes	1,222	357
Net loss	($132,362)	($27,026)
Net loss per share attributable to common stockholders:	'	'
Basic	($0.23)	($0.21)
Diluted	($0.23)	($0.21)
Weighted-average shares used to compute net loss per share attributable to common stockholders:	'	'
Basic	570,205	127,456
Diluted	570,205	127,456

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net loss	($132,362)	($27,026)
Other comprehensive income (loss):	'	'
Unrealized loss on investments in available-for-sale securities, net of tax	-31	-13
Foreign currency translation adjustment	58	-91
Net change in accumulated other comprehensive loss	27	-104
Comprehensive loss	($132,335)	($27,130)

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities	'	'
Net loss	($132,362)	($27,026)
Adjustments to reconcile net loss to net cash provided by operating activities:	'	'
Depreciation and amortization	39,951	22,730
Stock-based compensation expense	126,369	12,922
Provision for bad debt	778	226
Deferred income tax benefit	10	-436
Non-cash acquisition-related costs	'	566
Amortization of investment premium and other	2,255	1,649
Changes in assets and liabilities, net of assets acquired and liabilities assumed from acquisitions:	'	'
Accounts receivable	8,861	-972
Prepaid expenses and other assets	-30,415	-3,724
Accounts payable	-303	-4,420
Accrued and other liabilities	27,539	1,100
Net cash provided by operating activities	42,683	2,615
Cash flows from investing activities	'	'
Purchases of property and equipment, net of proceeds from sales	-49,620	-11,622
Purchases of marketable securities	-470,750	-140,768
Proceeds from maturities of marketable securities	477,333	70,191
Proceeds from sales of marketable securities	168,138	6,000
Restricted cash	-12,138	-1,125
Business combinations, net of cash acquired	'	178
Net cash provided by (used in) investing activities	112,963	-77,146
Cash flows from financing activities	'	'
Taxes paid related to net share settlement of equity awards	-15,140	'
Repayments of capital lease obligations	-21,521	-14,658
Proceeds from exercise of stock options and sales of restricted stock to employees at fair value, net of repurchase	1,350	4,739
Payments of offering costs	-1,162	'
Net cash used in financing activities	-36,473	-9,919
Net increase (decrease) in cash and cash equivalents	119,173	-84,450
Foreign exchange effect on cash and cash equivalents	572	-630
Cash and cash equivalents at beginning of period	841,010	203,328
Cash and cash equivalents at end of period	960,755	118,248
Supplemental disclosures of non-cash investing and financing activities	'	'
Common and convertible preferred stock issued in connection with acquisitions	'	105,467
Equipment purchases under capital leases	16,957	29,986
Changes in accrued equipment purchases	$11,051	$3,889

Description_of_Business_and_Su

Description of Business and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2014
Description of Business and Summary of Significant Accounting Policies	'
	Note 1. Description of Business and Summary of Significant Accounting Policies
	Twitter, Inc. (“Twitter” or the “Company”) was incorporated in Delaware in April 2007, and is headquartered in San Francisco, California. Twitter is a public platform where any user can create a Tweet and any user can follow other users. Each Tweet is limited to 140 characters of text, but can also contain rich media, including photos, videos and applications.
	Basis of Presentation
	The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation.
	The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (U.S. GAAP). The unaudited interim consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and reflect, in management’s opinion, all adjustments of a normal, recurring nature that are necessary for the fair statement of the Company’s financial position, results of operations and cash flows for the interim periods, but are not necessarily indicative of the results expected for the full fiscal year or any other period.
	The accompanying interim consolidated financial statements and these related notes should be read in conjunction with the consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
	Use of Estimates
	The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, as well as related disclosure of contingent assets and liabilities. Actual results could differ materially from the Company’s estimates. To the extent that there are material differences between these estimates and actual results, the Company’s financial condition or operating results will be affected. The Company bases its estimates on past experience and other assumptions that the Company believes are reasonable under the circumstances, and the Company evaluates these estimates on an ongoing basis.
	Recent Accounting Pronouncements
	In July 2013, the FASB issued a new accounting standard update on the financial statement presentation of unrecognized tax benefits. The new guidance provides that a liability related to an unrecognized tax benefit would be presented as a reduction of a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward, if such settlement is required or expected in the event the uncertain tax position is disallowed. The Company adopted this guidance prospectively for unrecognized tax benefits as of January 1, 2014. The adoption of this guidance resulted in a $15.8 million decrease in net deferred tax assets and the related liability for unrecognized tax benefits.

Cash_Cash_Equivalents_and_Shor

Cash, Cash Equivalents and Short-term Investments	3 Months Ended
	Mar. 31, 2014
Cash, Cash Equivalents and Short-term Investments	'
	Note 2. Cash, Cash Equivalents and Short-term Investments
	Cash, cash equivalents and short-term investments consist of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Cash and cash equivalents:
	Cash	$	223,173	$	164,135
	Money market funds		372,341		229,529
	U.S. government and agency securities including treasury bills		220,252		251,593
	Corporate notes and commercial paper		144,989		195,753
	Total cash and cash equivalents	$	960,755	$	841,010
	Short-term investments:
	U.S. government and agency securities including treasury bills	$	591,668	$	785,536
	Corporate notes, certificates of deposit and commercial paper		624,172		607,508
	Total short-term investments	$	1,215,840	$	1,393,044
	The following tables summarize unrealized gains and losses related to available-for-sale securities classified as short-term investments on the Company’s consolidated balance sheets (in thousands):
		31-Mar-14
		Gross		Gross			Gross			Aggregated
		Amortized		Unrealized			Unrealized			Estimated
		Costs		Gains			Losses			Fair Value
	US Government and agency securities including	$	591,631	$	47		$	(10	)	$	591,668
	treasury bills
	Corporate notes, certificates of deposit and		624,323		19			(170	)		624,172
	commercial paper
	Total available-for-sale securities classified as	$	1,215,954	$	66		$	(180	)	$	1,215,840
	short-term investments
		31-Dec-13
		Gross		Gross			Gross			Aggregated
		Amortized		Unrealized			Unrealized			Estimated
		Costs		Gains			Losses			Fair Value
	US Government and agency securities including	$	785,535	$	22		$	(21	)	$	785,536
	treasury bills
	Corporate notes, certificates of deposit and		607,590		11			(93	)		607,508
	commercial paper
	Total available-for-sale securities classified as	$	1,393,125	$	33		$	(114	)	$	1,393,044
	short-term investments
	The available-for-sale securities classified as cash and cash equivalents on the consolidated balance sheets are not included in the tables above as the gross unrealized gains and losses were immaterial for each period; their carrying value approximates fair value because of the short maturity period of these instruments.
	The following tables show all short-term investments in an unrealized loss position for which other-than-temporary impairment has not been recognized and the related gross unrealized losses and fair value, aggregated by investment category and the length of time that individual securities have been in a continuous unrealized loss position (in thousands):
		31-Mar-14
		Less than 12 Months					12 Months or Greater					Total
				Unrealized						Unrealized				Unrealized
		Fair Value		Loss			Fair Value			Loss		Fair Value		Loss
	US Government and agency securities	$	166,119	$	(10	)	$	—		$	—	$	166,119	$	(10	)
	including treasury bills
	Corporate notes, certificates of deposit		205,690		(170	)		—			—		205,690		(170	)
	and commercial paper
	Total short-term investments in an	$	371,809	$	(180	)	$	—		$	—	$	371,809	$	(180	)
	unrealized loss position
		31-Dec-13
		Less than 12 Months					12 Months or Greater					Total
				Unrealized						Unrealized				Unrealized
		Fair Value		Loss			Fair Value			Loss		Fair Value		Loss
	US Government and agency securities	$	230,478	$	(21	)	$	—		$	—	$	230,478	$	(21	)
	including treasury bills
	Corporate notes, certificates of deposit		171,894		(93	)		—			—		171,894		(93	)
	and commercial paper
	Total short-term investments in an	$	402,372	$	(114	)	$	—		$	—	$	402,372	$	(114	)
	unrealized loss position
	Investments are reviewed periodically to identify possible other-than-temporary impairments. No impairment loss has been recorded on the securities included in the tables above as the Company believes that the decrease in fair value of these securities is temporary and expects to recover up to (or beyond) the initial cost of investment for these securities.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2014
Fair Value Measurements	'
	Note 3. Fair Value Measurements
	The following tables set forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013 based on the three-tier fair value hierarchy (in thousands):
		31-Mar-14
		Level 1		Level 2		Level 3		Total
	Assets
	Cash equivalents:
	Money market funds	$	372,341	$	—	$	—	$	372,341
	Treasury bills		215,246		—		—		215,246
	Commercial paper		—		142,486		—		142,486
	U.S. government securities		—		5,006		—		5,006
	Corporate notes		—		2,503		—		2,503
	Short-term investments:
	Treasury bills		100,047		—		—		100,047
	Agency securities		—		2,000		—		2,000
	Commercial paper		—		271,115		—		271,115
	Corporate notes		—		277,120		—		277,120
	U.S. government securities		—		489,621		—		489,621
	Certificates of deposit		—		75,937		—		75,937
	Total	$	687,634	$	1,265,788	$	—	$	1,953,422
		31-Dec-13
		Level 1		Level 2		Level 3		Total
	Assets
	Cash equivalents:
	Money market funds	$	229,529	$	—	$	—	$	229,529
	Treasury bills		244,048		—		—		244,048
	Commercial paper		—		194,742		—		194,742
	U.S. government securities		—		7,545		—		7,545
	Corporate notes		—		1,011		—		1,011
	Short-term investments:
	Treasury bills		265,878		—		—		265,878
	Agency securities		—		18,286		—		18,286
	Commercial paper		—		272,617		—		272,617
	Corporate notes		—		255,546		—		255,546
	U.S. government securities		—		501,372		—		501,372
	Certificates of deposit		—		79,345		—		79,345
	Total	$	739,455	$	1,330,464	$	—	$	2,069,919

Property_and_Equipment_Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2014
Property and Equipment, Net	'
	Note 4. Property and Equipment, Net
	The following table presents the detail of property and equipment, net for the periods presented (in thousands):
		March 31,			December 31,
		2014			2013
	Property and equipment, net
	Equipment	$	410,549		$	367,949
	Furniture and leasehold improvements		67,418			54,965
	Capitalized software		56,512			47,290
	Construction in progress		48,786			29,523
	Total		583,265			499,727
	Less: Accumulated depreciation and amortization		(199,993	)		(167,065	)
	Property and equipment, net	$	383,272		$	332,662

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	3 Months Ended
	Mar. 31, 2014
Goodwill and Other Intangible Assets	'
	Note 5. Goodwill and Other Intangible Assets
	The goodwill balance was $363.5 million as of March 31, 2014 and December 31, 2013. For each of the period presented, gross goodwill balance equaled the net balance since no impairment charges have been recorded.
	The following table presents the detail of other intangible assets for the periods presented (in thousands):
		Gross Carrying		Accumulated			Net
		Value		Amortization			Carrying Value
	March 31, 2014:
	Patents and developed technologies	$	100,553	$	(49,581	)	$	50,972
	Publisher and advertiser relationships		21,100		(3,006	)		18,094
	Assembled workforce		1,960		(440	)		1,520
	Other intangible assets		1,100		(235	)		865
	Total	$	124,713	$	(53,262	)	$	71,451
	December 31, 2013:
	Patents and developed technologies	$	100,553	$	(45,440	)	$	55,113
	Publisher and advertiser relationships		21,100		(1,248	)		19,852
	Assembled workforce		1,960		(300	)		1,660
	Other intangible assets		1,100		(98	)		1,002
	Total	$	124,713	$	(47,086	)	$	77,627
	Amortization expense associated with other intangible assets for the three months ended March 31, 2014 and 2013 was $6.2 million and $3.9 million, respectively.
	Estimated future amortization expense as of March 31, 2014 is as follows (in thousands):
	Remainder of 2014	$	15,095
	2015		16,726
	2016		13,421
	2017		3,264
	2018		3,264
	Thereafter		19,681
	Total	$	71,451

Other_Balance_Sheet_Components

Other Balance Sheet Components	3 Months Ended
	Mar. 31, 2014
Other Balance Sheet Components	'
	Note 6. Other Balance Sheet Components
	Prepaid and other current assets
	The following table presents the detail of prepaid and other current assets for the periods presented (in thousands):
		March 31,		December 31,
		2014		2013
	Deferred income taxes, net	$	31,382	$	62,122
	Prepaid and other		59,543		31,175
	Total	$	90,925	$	93,297
	Accrued and other current liabilities
	The following table presents the detail of accrued and other current liabilities for the periods presented (in thousands):
		March 31,		December 31,
		2014		2013
	Accrued compensation	$	50,829	$	29,882
	Accrued equipment and maintenance		19,468		2,890
	Deferred revenue		15,405		14,479
	Accrued publisher payments		13,547		15,370
	Accrued professional services		10,313		7,089
	Accrued tax liabilities		10,073		9,515
	Accrued equipment purchases under capital lease		711		2,807
	Accrued other		30,938		28,278
	Total	$	151,284	$	110,310

Net_Loss_Per_Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2014
Net Loss Per Share	'
	Note 7. Net Loss per Share
	The Company computes net loss per share of common stock in conformity with the two-class method required for participating securities. The Company considers the shares issued upon the early exercise of stock options subject to repurchase to be participating securities, because holders of such shares have non-forfeitable dividend rights in the event a dividend is paid on common stock. Prior to their conversion to common stock, the Company also considered all series of the Company’s redeemable convertible preferred stock and convertible preferred stock to be participating securities as the holders of the preferred stock were entitled to receive a noncumulative dividend on a pari passu basis in the event that a dividend was paid on common stock. The holders of all series of convertible preferred stock and the holders of early exercised shares subject to repurchase do not have a contractual obligation to share in the losses of the Company. As such, the Company’s net losses for the three months ended March 31, 2014 and 2013 were not allocated to these participating securities.
	Basic net loss per share is computed by dividing total net loss attributable to common stockholders by the weighted-average common shares outstanding. The weighted-average common shares outstanding is adjusted for shares subject to repurchase such as unvested restricted stock granted to employees in connection with acquisitions, contingently returnable shares and escrowed shares supporting indemnification obligations that are issued in connection with acquisitions and unvested stock options exercised. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding including potential dilutive common stock instruments. In the three months ended March 31, 2014 and 2013, the Company’s potential common stock instruments such as stock options, RSUs, ESPP, shares subject to repurchases and the warrant were not included in the computation of diluted loss per share as the effect of including these shares in the calculation would have been anti-dilutive.
	The following table presents the calculation of basic and diluted net loss per share for periods presented (in thousands, except per share data).
		Three Months Ended March 31,
		2014			2013
	Net loss	$	(132,362	)	$	(27,026	)
	Basic shares:
	Weighted-average common shares outstanding		579,128			132,957
	Weighted-average unvested restricted stock		(8,923	)		(5,501	)
	subject to repurchase
	Weighted-average shares used to compute		570,205			127,456
	basic net loss per share
	Diluted shares:
	Weighted-average shares used to compute		570,205			127,456
	diluted net loss per share
	Net loss per share attributable to common stockholders:
	Basic	$	(0.23	)	$	(0.21	)
	Diluted	$	(0.23	)	$	(0.21	)
	The following potential common shares were excluded from the calculation of diluted net loss per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented (in thousands):
		Three Months Ended March 31,
		2014			2013
	Stock options		39,796			45,465
	RSUs		83,232			11,038
	Employee stock purchase plans		1,868			—
	Shares subject to repurchase		7,898			7,486
	Warrant		117			117

Common_Stock_and_Stockholders_

Common Stock and Stockholders' Equity	3 Months Ended
	Mar. 31, 2014
Common Stock and Stockholders' Equity	'
	Note 8. Common Stock and Stockholders’ Equity
	Common Stock
	Each share of common stock is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when and if declared by the Board of Directors, subject to the prior rights of holders of all classes of stock outstanding. As of March 31, 2014, no dividends have been declared.
	Restricted Common Stock
	The Company has granted restricted common stock to certain key continuing employees in connection with the acquisitions. Vesting of this stock is dependent on the respective employee’s continued employment at the Company during the requisite service period, which is generally two to four years from the issuance date, and the Company has the option to repurchase the unvested shares upon termination of employment. The fair value of the restricted common stock issued to employees is recorded as compensation expense on a straight-line basis over the requisite service period.
	The activities for the restricted common stock issued to employees for the three month ended March 31, 2014 are summarized as follows (in thousands, except per share data):
						Weighted-Average
			Number of			Grant-Date Fair
			Shares			Value Per Share
	Unvested restricted common stock at December 31, 2013			6,866		$	17.6
	Granted			—		$	—
	Vested			(1,498	)	$	16.92
	Canceled			—		$	—
	Unvested restricted common stock at March 31, 2014			5,368		$	17.79
	During the three months ended March 31, 2014 and 2013, the Company recorded $11.1 million and $5.2 million, respectively, of compensation expense related to restricted common stock issued to employees. As of March 31, 2014, there was $73.4 million of unamortized stock-based compensation expense related to restricted common stock issued which is expected to be recognized over a weighted-average period of 2.19 years.
	Equity Incentive Plans
	As of March 31, 2014 the total number of RSUs outstanding under the 2013 Equity Incentive Plan was 13.7 million shares, and 85.2 million shares were available for future issuance. There were 110.0 million shares of options and RSUs outstanding under the 2007 Equity Incentive Plan as of March 31, 2014. No additional shares will be issued under the 2007 Equity Incentive Plan.
	Under the 2007 Equity Incentive Plan, RSUs granted to (i) international employees; and (ii) domestic employees prior to February 2013 (“Pre-2013 RSUs”) vest upon the satisfaction of both a service condition and a performance condition. The service condition for these awards is generally satisfied over four years. The performance condition was satisfied in February 2014 pursuant to the terms of the Company’s equity plan. An aggregate of 17.1 million shares of common stock were issued as a result of vesting and settlement of the Pre-2013 RSUs during the three months ended March 31, 2014.  During the same period, the Company's employees who are not executive officers were allowed to sell a portion of vested and settled Pre-2013 RSUs in the public market to satisfy the income tax obligations related to the vesting and settlement of such awards.  The proceeds from selling the shares required to satisfy the employees' minimum statutory obligation were withheld and remitted to the appropriate tax authorities.  In addition, the Company undertook a net settlement of vested Pre-2013 RSUs held by the executive officers upon satisfaction of the performance condition in February 2014 and withheld shares and remitted income tax on behalf of the applicable executive officers of $15.1 million in cash at the applicable minimum statutory rates.  These shares withheld by the Company as a result of the net settlement of Pre-2013 RSUs are no longer considered issued and outstanding.
	RSUs granted to domestic employees starting in February 2013 (“Post-2013 RSUs”) are not subject to a performance condition in order to vest. The majority of Post-2013 RSUs vest over a service period of four years. Under the terms of the 2007 and 2013 Equity Incentive Plan, the shares underlying Post-2013 RSUs that satisfy the service condition are to be delivered to holders no later than the fifteenth day of the third month following the end of the calendar year the service condition is satisfied, or if later, the end of the Company’s tax year, but no earlier than May 15, 2014.
	Employee Stock Purchase Plan
	As of March 31, 2014, no purchase has been made and 17.7 million shares were available for future issuance under the ESPP. During the three months ended March 31, 2014, the Company recorded $6.2 million of stock-based compensation expense related to the ESPP.
	Stock Option Activity
	A summary of stock option activity for the three months ended March 31, 2014 is as follows (in thousands, except years and per share data):
			Options Outstanding
									Weighted-
						Weighted-			Average
						Average			Remaining
			Number of			Exercise			Contractual Life		Aggregate
			Shares			Price Per Share			(in years)		Intrinsic Value
	Outstanding at December 31, 2013			42,246		$	1.89			6.47	$	2,609,295
	Options granted			—		$	—
	Options exercised			(2,282	)	$	0.59
	Options canceled			(168	)	$	6.7
	Outstanding at March 31, 2014			39,796		$	1.94			6.21	$	1,780,127
	Vested and expected to vest at			39,123		$	1.89			6.19	$	1,752,077
	March 31, 2014 (1)
	Exercisable at March 31, 2014			32,649		$	1.27			5.95	$	1,482,359
	-1	The expected to vest options are the result of applying pre-vesting forfeiture rate assumptions to unvested options outstanding.
	The aggregate intrinsic value in the table above represents the difference between the estimated fair value of common stock and the exercise price of outstanding, in-the-money stock options.
	The total intrinsic value of stock options exercised during the three months ended March 31, 2014 and 2013 were $133.9 million and $57.3 million, respectively. The total fair value of stock options vested during the three months ended March 31, 2014 and 2013 were $3.5 million and $3.9 million, respectively.
	RSU Activity
	The following table summarizes the activity related to the Company’s Pre- and Post-2013 RSUs for the three months ended March 31, 2014. For purposes of this table, vested RSUs represent the shares for which the service condition had been fulfilled as of each respective date (in thousands, except per share data):
			RSUs Outstanding
						Weighted-
						Average Grant-
						Date Fair Value
			Shares			Per Share
	Unvested and outstanding at December 31, 2013			79,876		$	19.54
	Granted			8,779		$	53.84
	Vested			(4,434	)	$	16.43
	Canceled			(989	)	$	16.46
	Unvested and outstanding at March 31, 2014			83,232		$	23.36
	Vested and outstanding at March 31, 2014			2,921		$	16.97
	Stock-Based Compensation Expense
	Total stock-based compensation expense recorded for employee and non-employee stock options, RSUs, ESPP and restricted common stock and Class A junior preferred stock in the three months ended March 31, 2014 and 2013 is summarized as follows (in thousands):
			Three Months Ended March 31,
			2014			2013
	Employee		$	125,969		$	12,127
	Non-employee			400			795
	Total		$	126,369		$	12,922
	The compensation expense is allocated based on the cost center the award holder belongs to. Total stock-based compensation expense by function is as follows (in thousands):
			Three Months Ended March 31,
			2014			2013
Cost of revenue		$	9,831		$	484
Research and development			78,318			8,425
Sales and marketing			27,801			2,065
General and administrative			10,419			1,948
Total		$	126,369		$	12,922
The Company capitalized $6.7 million and $1.4 million of stock-based compensation expense associated with the cost for developing software for internal use in the three months ended March 31, 2014 and 2013, respectively.
The weighted-average grant-date fair value of stock options granted to employees in the three month ended March 31, 2013 was $11.13 per share. The Company did not grant additional options to employees during the three month ended March 31, 2014. The fair value of stock options granted to employees was determined using the Black-Scholes option pricing model with the following weighted-average assumptions:
		Three Months Ended March 31,
		2014			2013
Expected dividend yield			N/A			—
Risk-free interest rate			N/A			1.07	%
Expected volatility			N/A			53.77	%
Expected term (in years)			N/A			5.63
As of March 31, 2014, there was $28.9 million of unamortized stock-based compensation expense related to unvested stock options granted to employees and non-employee service providers which is expected to be recognized over a weighted-average period of 1.93 years. The unamortized stock-based compensation expense related to Pre- and Post-2013 RSUs of $126.9 million and $1.2 billion, respectively, as of March 31, 2014 is expected to be recognized over a weighted-average period of 2.45 years and 3.20 years, respectively. $22.5 million of unamortized stock-based compensation expense related to ESPP is expected to be recognized over a period of 0.63 years.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2014
Income Taxes	'
	Note 9. Income Taxes
	The Company is subject to taxation in the United States and various state and foreign jurisdictions. Earnings from non-US activities are subject to local country income tax. The material jurisdictions in which the Company is subject to potential examination by taxing authorities include the United States, California and Ireland. The Company is currently under an income tax examination in California for tax years 2010 and 2011. The Company believes that adequate amounts have been reserved in these jurisdictions. The Company does not provide for federal income taxes on the undistributed earnings of its foreign subsidiaries as such earnings are to be reinvested indefinitely outside the U.S. The Company computes its quarterly income tax provision by using a forecasted annual effective tax rate and adjusts for any discrete items arising during the quarter.
	The Company recorded income tax expense of $1.2 million and $0.4 million for the three months ended March 31, 2014 and 2013, respectively. The tax provision increased in the three months ended March 31, 2014 compared to the same period last year, primarily due to increased foreign tax expense and state income taxes.  As of March 31, 2014, based on the available objective evidence, management believes it is more likely than not that the tax benefits of the U.S. losses incurred during the three months ended March 31, 2014 will not be realized by the end of the 2014 fiscal year. Accordingly, the Company did not record the tax benefits of the U.S. losses incurred during the first quarter ended March 31, 2014. The primary difference between the effective tax rate and the federal statutory tax rate relates to the valuation allowances on the Company’s net operating losses and foreign tax rate differences.
	During the three months ended March 31, 2014, the amount of gross unrecognized tax benefits increased by $18.3 million. As of March 31, 2014, the Company has $61.4 million of unrecognized tax benefits which are subject to full valuation allowance and, if recognized, will not affect the annual effective tax rate.
	As a result of employee RSUs vesting in the quarter ended March 31, 2014, the Company’s federal and state net operating loss carryforwards increased by approximately $916.4 million and $241.3 million, respectively.  The portion of the increased net operating loss carryforwards related to excess federal and state tax benefits from the RSUs is approximately $677.5 million and $178.4 million, respectively, the benefit of which will be credited to additional paid-in capital when realized.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies	'
	Note 10. Commitments and Contingencies
	Credit Facility
	The Company entered into a revolving credit agreement with certain lenders in 2013, which provided for a $1.0 billion revolving unsecured credit facility maturing on October 22, 2018. Loans under the credit facility bear interest, at the Company’s option, at (i) a base rate based on the highest of the prime rate, the federal funds rate plus 0.50% and an adjusted LIBOR rate for a one-month interest period plus 1.00%, in each case plus a margin ranging from 0.00% to 0.75% or (ii) an adjusted LIBOR rate plus a margin ranging from 1.00% to 1.75%. This margin is determined based on the total leverage ratio for the preceding four fiscal quarter period. The Company is obligated to pay other customary fees for a credit facility of this size and type, including an upfront fee and an unused commitment fee. Obligations under the credit facility are guaranteed by one of the Company’s wholly-owned subsidiaries. As of March 31, 2014, no amounts were drawn under the credit facility.
	Operating and Capital Leases
	The Company has entered into various non-cancelable operating lease agreements for certain offices and data center facilities with contractual lease periods expiring between 2014 and 2031.
	A summary of gross and net lease commitments as of March 31, 2014 is as follows (in thousands):
		Operating		Capital
		Leases		Leases
	Remainder of 2014	$	55,958	$	72,904
	2015		98,691		78,520
	2016		109,604		40,570
	2017		109,972		12,666
	2018		104,676		235
	Thereafter		268,266		—
		$	747,167		204,895
	Less: Amounts representing interest				12,108
	Total capital lease obligation				192,787
	Less: Short-term portion				90,253
	Long-term portion			$	102,534
	Legal Proceedings
	The Company is currently involved in, and may in the future be involved in, legal proceedings, claims and governmental investigations in the normal course of business. Legal fees and other costs associated with such actions are expensed as incurred. The Company assesses, in conjunction with its legal counsel, the need to record a liability for litigation and contingencies. Litigation accruals are recorded when and if it is determined that a loss related matter is both probable and reasonably estimable. Material loss contingencies that are reasonably possible of occurrence, if any, are subject to disclosure. As of March 31, 2014 and December 31, 2013, there was no litigation or contingency with at least a reasonable possibility of a material loss. No losses have been recorded during three months ended March 31, 2014 and 2013 with respect to litigation or loss contingencies.
	Indemnification
	In the ordinary course of business, the Company often includes standard indemnification provisions in its arrangements with its customers, partners, suppliers and vendors. Pursuant to these provisions, the Company may be obligated to indemnify such parties for losses or claims suffered or incurred in connection with its service, breach of representations or covenants, intellectual property infringement or other claims made against such parties. These provisions may limit the time within which an indemnification claim can be made. It is not possible to determine the maximum potential amount under these indemnification obligations due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement. The Company has never incurred significant expense defending its licensees against third party claims, nor has it ever incurred significant expense under its standard service warranties or arrangements with its customers, partners, suppliers and vendors. Accordingly, the Company had no liabilities recorded for these provisions as of March 31, 2014 and December 31, 2013.

Operations_by_Geographic_Area

Operations by Geographic Area	3 Months Ended
	Mar. 31, 2014
Operations by Geographic Area	'
	Note 11. Operations by Geographic Area
	Revenue
	Revenue by geography is based on the billing addresses of the customers. The following table sets forth revenue by geographic area (in thousands):
		Three Months Ended March 31,
		2014		2013
	Revenue:
	United States	$	180,039	$	89,416
	International		70,453		24,927
	Total revenue	$	250,492	$	114,343
	No individual country from the international markets contributed in excess of 10% of the total revenue for the three months ended March 31, 2014 and March 31, 2013.
	Long-Lived Assets
	The following table sets forth long-lived assets by geographic area (in thousands):
		March 31,		December 31,
		2014		2013
	Long-lived assets:
	United States	$	376,271	$	327,250
	International		7,001		5,412
	Total long-lived assets	$	383,272	$	332,662

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2014
Subsequent Events	'
	Note 12. Subsequent Events
	From April 1, 2014 to May 8, 2014, the Company completed acquisitions of four privately held companies.  Under the terms of these acquisitions, the Company agreed to issue a total of 1.6 million shares of the Company's common stock and pay approximately $144.2 million in cash.  In addition, outstanding stock options held by the acquired companies' employees, who will continue to provide services to the Company, were converted into the right to receive an aggregate of 0.5 million shares of the Company's stock options.

Description_of_Business_and_Su1

Description of Business and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2014
Basis of Presentation	'
	Basis of Presentation
	The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation.
	The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (U.S. GAAP). The unaudited interim consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and reflect, in management’s opinion, all adjustments of a normal, recurring nature that are necessary for the fair statement of the Company’s financial position, results of operations and cash flows for the interim periods, but are not necessarily indicative of the results expected for the full fiscal year or any other period.
	The accompanying interim consolidated financial statements and these related notes should be read in conjunction with the consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
Use of Estimates	'
	Use of Estimates
	The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, as well as related disclosure of contingent assets and liabilities. Actual results could differ materially from the Company’s estimates. To the extent that there are material differences between these estimates and actual results, the Company’s financial condition or operating results will be affected. The Company bases its estimates on past experience and other assumptions that the Company believes are reasonable under the circumstances, and the Company evaluates these estimates on an ongoing basis.
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In July 2013, the FASB issued a new accounting standard update on the financial statement presentation of unrecognized tax benefits. The new guidance provides that a liability related to an unrecognized tax benefit would be presented as a reduction of a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward, if such settlement is required or expected in the event the uncertain tax position is disallowed. The Company adopted this guidance prospectively for unrecognized tax benefits as of January 1, 2014. The adoption of this guidance resulted in a $15.8 million decrease in net deferred tax assets and the related liability for unrecognized tax benefits.

Cash_Cash_Equivalents_and_Shor1

Cash, Cash Equivalents and Short-term Investments (Tables)	3 Months Ended
	Mar. 31, 2014
Cash, Cash and Equivalents and Short-term Investments	'
	Cash, cash equivalents and short-term investments consist of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Cash and cash equivalents:
	Cash	$	223,173	$	164,135
	Money market funds		372,341		229,529
	U.S. government and agency securities including treasury bills		220,252		251,593
	Corporate notes and commercial paper		144,989		195,753
	Total cash and cash equivalents	$	960,755	$	841,010
	Short-term investments:
	U.S. government and agency securities including treasury bills	$	591,668	$	785,536
	Corporate notes, certificates of deposit and commercial paper		624,172		607,508
	Total short-term investments	$	1,215,840	$	1,393,044
Summary of Unrealized Gains and Losses Related to Available-for-Sale Securities Classified as Short-term Investments	'
	The following tables summarize unrealized gains and losses related to available-for-sale securities classified as short-term investments on the Company’s consolidated balance sheets (in thousands):
		31-Mar-14
		Gross		Gross			Gross			Aggregated
		Amortized		Unrealized			Unrealized			Estimated
		Costs		Gains			Losses			Fair Value
	US Government and agency securities including	$	591,631	$	47		$	(10	)	$	591,668
	treasury bills
	Corporate notes, certificates of deposit and		624,323		19			(170	)		624,172
	commercial paper
	Total available-for-sale securities classified as	$	1,215,954	$	66		$	(180	)	$	1,215,840
	short-term investments
		31-Dec-13
		Gross		Gross			Gross			Aggregated
		Amortized		Unrealized			Unrealized			Estimated
		Costs		Gains			Losses			Fair Value
	US Government and agency securities including	$	785,535	$	22		$	(21	)	$	785,536
	treasury bills
	Corporate notes, certificates of deposit and		607,590		11			(93	)		607,508
	commercial paper
	Total available-for-sale securities classified as	$	1,393,125	$	33		$	(114	)	$	1,393,044
	short-term investments
Summary of Short-term Investments in Unrealized Loss Position and Related Gross Unrealized Losses and Fair Value, Aggregated by Investment Category and Length of Time	'
	The following tables show all short-term investments in an unrealized loss position for which other-than-temporary impairment has not been recognized and the related gross unrealized losses and fair value, aggregated by investment category and the length of time that individual securities have been in a continuous unrealized loss position (in thousands):
		31-Mar-14
		Less than 12 Months					12 Months or Greater					Total
				Unrealized						Unrealized				Unrealized
		Fair Value		Loss			Fair Value			Loss		Fair Value		Loss
	US Government and agency securities	$	166,119	$	(10	)	$	—		$	—	$	166,119	$	(10	)
	including treasury bills
	Corporate notes, certificates of deposit		205,690		(170	)		—			—		205,690		(170	)
	and commercial paper
	Total short-term investments in an	$	371,809	$	(180	)	$	—		$	—	$	371,809	$	(180	)
	unrealized loss position
		31-Dec-13
		Less than 12 Months					12 Months or Greater					Total
				Unrealized						Unrealized				Unrealized
		Fair Value		Loss			Fair Value			Loss		Fair Value		Loss
	US Government and agency securities	$	230,478	$	(21	)	$	—		$	—	$	230,478	$	(21	)
	including treasury bills
	Corporate notes, certificates of deposit		171,894		(93	)		—			—		171,894		(93	)
	and commercial paper
	Total short-term investments in an	$	402,372	$	(114	)	$	—		$	—	$	402,372	$	(114	)
	unrealized loss position

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2014
Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	'
	The following tables set forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013 based on the three-tier fair value hierarchy (in thousands):
		31-Mar-14
		Level 1		Level 2		Level 3		Total
	Assets
	Cash equivalents:
	Money market funds	$	372,341	$	—	$	—	$	372,341
	Treasury bills		215,246		—		—		215,246
	Commercial paper		—		142,486		—		142,486
	U.S. government securities		—		5,006		—		5,006
	Corporate notes		—		2,503		—		2,503
	Short-term investments:
	Treasury bills		100,047		—		—		100,047
	Agency securities		—		2,000		—		2,000
	Commercial paper		—		271,115		—		271,115
	Corporate notes		—		277,120		—		277,120
	U.S. government securities		—		489,621		—		489,621
	Certificates of deposit		—		75,937		—		75,937
	Total	$	687,634	$	1,265,788	$	—	$	1,953,422
		31-Dec-13
		Level 1		Level 2		Level 3		Total
	Assets
	Cash equivalents:
	Money market funds	$	229,529	$	—	$	—	$	229,529
	Treasury bills		244,048		—		—		244,048
	Commercial paper		—		194,742		—		194,742
	U.S. government securities		—		7,545		—		7,545
	Corporate notes		—		1,011		—		1,011
	Short-term investments:
	Treasury bills		265,878		—		—		265,878
	Agency securities		—		18,286		—		18,286
	Commercial paper		—		272,617		—		272,617
	Corporate notes		—		255,546		—		255,546
	U.S. government securities		—		501,372		—		501,372
	Certificates of deposit		—		79,345		—		79,345
	Total	$	739,455	$	1,330,464	$	—	$	2,069,919

Property_and_Equipment_Net_Tab

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2014
Schedule of Property and Equipment, Net	'
	The following table presents the detail of property and equipment, net for the periods presented (in thousands):
		March 31,			December 31,
		2014			2013
	Property and equipment, net
	Equipment	$	410,549		$	367,949
	Furniture and leasehold improvements		67,418			54,965
	Capitalized software		56,512			47,290
	Construction in progress		48,786			29,523
	Total		583,265			499,727
	Less: Accumulated depreciation and amortization		(199,993	)		(167,065	)
	Property and equipment, net	$	383,272		$	332,662

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2014
Schedule of Other Intangible Assets	'
	The following table presents the detail of other intangible assets for the periods presented (in thousands):
		Gross Carrying		Accumulated			Net
		Value		Amortization			Carrying Value
	March 31, 2014:
	Patents and developed technologies	$	100,553	$	(49,581	)	$	50,972
	Publisher and advertiser relationships		21,100		(3,006	)		18,094
	Assembled workforce		1,960		(440	)		1,520
	Other intangible assets		1,100		(235	)		865
	Total	$	124,713	$	(53,262	)	$	71,451
	December 31, 2013:
	Patents and developed technologies	$	100,553	$	(45,440	)	$	55,113
	Publisher and advertiser relationships		21,100		(1,248	)		19,852
	Assembled workforce		1,960		(300	)		1,660
	Other intangible assets		1,100		(98	)		1,002
	Total	$	124,713	$	(47,086	)	$	77,627
Schedule of Estimated Future Amortization Expenses	'
	Estimated future amortization expense as of March 31, 2014 is as follows (in thousands):
	Remainder of 2014	$	15,095
	2015		16,726
	2016		13,421
	2017		3,264
	2018		3,264
	Thereafter		19,681
	Total	$	71,451

Other_Balance_Sheet_Components1

Other Balance Sheet Components (Tables)	3 Months Ended
	Mar. 31, 2014
Prepaid and Other Current Assets	'
	The following table presents the detail of prepaid and other current assets for the periods presented (in thousands):
		March 31,		December 31,
		2014		2013
	Deferred income taxes, net	$	31,382	$	62,122
	Prepaid and other		59,543		31,175
	Total	$	90,925	$	93,297
Accrued and Other Current Liabilities	'
	The following table presents the detail of accrued and other current liabilities for the periods presented (in thousands):
		March 31,		December 31,
		2014		2013
	Accrued compensation	$	50,829	$	29,882
	Accrued equipment and maintenance		19,468		2,890
	Deferred revenue		15,405		14,479
	Accrued publisher payments		13,547		15,370
	Accrued professional services		10,313		7,089
	Accrued tax liabilities		10,073		9,515
	Accrued equipment purchases under capital lease		711		2,807
	Accrued other		30,938		28,278
	Total	$	151,284	$	110,310

Net_Loss_Per_Share_Tables

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2014
Basic and Diluted Net Loss Per Share	'
	The following table presents the calculation of basic and diluted net loss per share for periods presented (in thousands, except per share data).
		Three Months Ended March 31,
		2014			2013
	Net loss	$	(132,362	)	$	(27,026	)
	Basic shares:
	Weighted-average common shares outstanding		579,128			132,957
	Weighted-average unvested restricted stock		(8,923	)		(5,501	)
	subject to repurchase
	Weighted-average shares used to compute		570,205			127,456
	basic net loss per share
	Diluted shares:
	Weighted-average shares used to compute		570,205			127,456
	diluted net loss per share
	Net loss per share attributable to common stockholders:
	Basic	$	(0.23	)	$	(0.21	)
	Diluted	$	(0.23	)	$	(0.21	)
Summary of Potential Common Shares Excluded from Calculation of Diluted Net Loss Per Share Attributable to Common Stockholders	'
	The following potential common shares were excluded from the calculation of diluted net loss per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented (in thousands):
		Three Months Ended March 31,
		2014			2013
	Stock options		39,796			45,465
	RSUs		83,232			11,038
	Employee stock purchase plans		1,868			—
	Shares subject to repurchase		7,898			7,486
	Warrant		117			117

Common_Stock_and_Stockholders_1

Common Stock and Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2014
Summary of Restricted Stock Activity	'
	The activities for the restricted common stock issued to employees for the three month ended March 31, 2014 are summarized as follows (in thousands, except per share data):
					Weighted-Average
		Number of			Grant-Date Fair
		Shares			Value Per Share
	Unvested restricted common stock at December 31, 2013		6,866		$	17.6
	Granted		—		$	—
	Vested		(1,498	)	$	16.92
	Canceled		—		$	—
	Unvested restricted common stock at March 31, 2014		5,368		$	17.79
Summary of Stock Option Activity	'
	A summary of stock option activity for the three months ended March 31, 2014 is as follows (in thousands, except years and per share data):
		Options Outstanding
								Weighted-
					Weighted-			Average
					Average			Remaining
		Number of			Exercise			Contractual Life		Aggregate
		Shares			Price Per Share			(in years)		Intrinsic Value
	Outstanding at December 31, 2013		42,246		$	1.89			6.47	$	2,609,295
	Options granted		—		$	—
	Options exercised		(2,282	)	$	0.59
	Options canceled		(168	)	$	6.7
	Outstanding at March 31, 2014		39,796		$	1.94			6.21	$	1,780,127
	Vested and expected to vest at		39,123		$	1.89			6.19	$	1,752,077
	March 31, 2014 (1)
	Exercisable at March 31, 2014		32,649		$	1.27			5.95	$	1,482,359
Summary of RSU Activity	'
	The following table summarizes the activity related to the Company’s Pre- and Post-2013 RSUs for the three months ended March 31, 2014. For purposes of this table, vested RSUs represent the shares for which the service condition had been fulfilled as of each respective date (in thousands, except per share data):
		RSUs Outstanding
					Weighted-
					Average Grant-
					Date Fair Value
		Shares			Per Share
	Unvested and outstanding at December 31, 2013		79,876		$	19.54
	Granted		8,779		$	53.84
	Vested		(4,434	)	$	16.43
	Canceled		(989	)	$	16.46
	Unvested and outstanding at March 31, 2014		83,232		$	23.36
	Vested and outstanding at March 31, 2014		2,921		$	16.97
Stock-Based Compensation Expense Recorded for Employee and Non-Employee Stock Options	'
	Total stock-based compensation expense recorded for employee and non-employee stock options, RSUs, ESPP and restricted common stock and Class A junior preferred stock in the three months ended March 31, 2014 and 2013 is summarized as follows (in thousands):
		Three Months Ended March 31,
		2014			2013
	Employee	$	125,969		$	12,127
	Non-employee		400			795
	Total	$	126,369		$	12,922
Compensation Expense Allocated	'
	The compensation expense is allocated based on the cost center the award holder belongs to. Total stock-based compensation expense by function is as follows (in thousands):
		Three Months Ended March 31,
		2014			2013
	Cost of revenue	$	9,831		$	484
	Research and development		78,318			8,425
	Sales and marketing		27,801			2,065
	General and administrative		10,419			1,948
	Total	$	126,369		$	12,922
Schedule of Share-based Payment Award, Valuation Assumptions	'
	The weighted-average grant-date fair value of stock options granted to employees in the three month ended March 31, 2013 was $11.13 per share. The Company did not grant additional options to employees during the three month ended March 31, 2014. The fair value of stock options granted to employees was determined using the Black-Scholes option pricing model with the following weighted-average assumptions:
		Three Months Ended March 31,
		2014			2013
	Expected dividend yield		N/A			—
	Risk-free interest rate		N/A			1.07	%
	Expected volatility		N/A			53.77	%
	Expected term (in years)		N/A			5.63

Commitment_and_Contingencies_T

Commitment and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2014
Minimum Commitments Under Non-Cancelable Capital and Operating Lease Agreements	'
	A summary of gross and net lease commitments as of March 31, 2014 is as follows (in thousands):
		Operating		Capital
		Leases		Leases
	Remainder of 2014	$	55,958	$	72,904
	2015		98,691		78,520
	2016		109,604		40,570
	2017		109,972		12,666
	2018		104,676		235
	Thereafter		268,266		—
		$	747,167		204,895
	Less: Amounts representing interest				12,108
	Total capital lease obligation				192,787
	Less: Short-term portion				90,253
	Long-term portion			$	102,534

Operations_by_Geographic_Area_

Operations by Geographic Area (Tables)	3 Months Ended
	Mar. 31, 2014
Revenue by Geography	'
	Revenue by geography is based on the billing addresses of the customers. The following table sets forth revenue by geographic area (in thousands):
		Three Months Ended March 31,
		2014		2013
	Revenue:
	United States	$	180,039	$	89,416
	International		70,453		24,927
	Total revenue	$	250,492	$	114,343
Long-lived Assets by Geographic Area	'
	The following table sets forth long-lived assets by geographic area (in thousands):
		March 31,		December 31,
		2014		2013
	Long-lived assets:
	United States	$	376,271	$	327,250
	International		7,001		5,412
	Total long-lived assets	$	383,272	$	332,662

Description_of_Business_and_Su2

Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) (USD $)	Mar. 31, 2014
In Millions, unless otherwise specified
Decrease in net deferred tax assets and liability	($15.80)

Cash_Cash_Equivalents_and_Shor2

Cash, Cash Equivalents and Short-term Investments - Cash, Cash and Equivalents and Short-term Investments (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Cash and cash equivalents:	'	'	'	'
Cash and cash equivalents	$960,755	$841,010	$118,248	$203,328
Short-term investments:	'	'	'	'
Short-term investments	1,215,840	1,393,044	'	'
Cash	'	'	'	'
Cash and cash equivalents:	'	'	'	'
Cash and cash equivalents	223,173	164,135	'	'
Money Market Funds	'	'	'	'
Cash and cash equivalents:	'	'	'	'
Cash and cash equivalents	372,341	229,529	'	'
U.S. Government and Agency Securities Including Treasury Bills	'	'	'	'
Cash and cash equivalents:	'	'	'	'
Cash and cash equivalents	220,252	251,593	'	'
Short-term investments:	'	'	'	'
Short-term investments	591,668	785,536	'	'
Corporate Notes, Certificates of Deposit and Commercial Paper	'	'	'	'
Cash and cash equivalents:	'	'	'	'
Cash and cash equivalents	144,989	195,753	'	'
Short-term investments:	'	'	'	'
Short-term investments	$624,172	$607,508	'	'

Cash_Cash_Equivalents_and_Shor3

Cash, Cash Equivalents and Short-term Investments - Summary of Unrealized Gains and Losses Related to Available-for-Sale Securities Classified as Short-term Investments (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule Of Available For Sale Securities [Line Items]	'	'
Gross Amortized Costs	$1,215,954	$1,393,125
Gross Unrealized Gains	66	33
Gross Unrealized Losses	-180	-114
Aggregated Estimated Fair Value	1,215,840	1,393,044
U.S. Government and Agency Securities Including Treasury Bills	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'
Gross Amortized Costs	591,631	785,535
Gross Unrealized Gains	47	22
Gross Unrealized Losses	-10	-21
Aggregated Estimated Fair Value	591,668	785,536
Corporate Notes, Certificates of Deposit and Commercial Paper	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'
Gross Amortized Costs	624,323	607,590
Gross Unrealized Gains	19	11
Gross Unrealized Losses	-170	-93
Aggregated Estimated Fair Value	$624,172	$607,508

Cash_Cash_Equivalents_and_Shor4

Cash, Cash Equivalents and Short-term Investments - Summary of Short-term Investments in Unrealized Loss Position and Related Gross Unrealized Losses and Fair Value, Aggregated by Investment Category and Length of Time (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule Of Available For Sale Securities [Line Items]	'	'
Less than 12 Months, Fair Value	$371,809	$402,372
Less than 12 Months, Unrealized Loss	-180	-114
12 Months or Greater, Fair Value	'	'
12 Months or Greater, Unrealized Loss	'	'
Total Fair Value	371,809	402,372
Total Unrealized Loss	-180	-114
U.S. Government and Agency Securities Including Treasury Bills	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'
Less than 12 Months, Fair Value	166,119	230,478
Less than 12 Months, Unrealized Loss	-10	-21
12 Months or Greater, Fair Value	'	'
12 Months or Greater, Unrealized Loss	'	'
Total Fair Value	166,119	230,478
Total Unrealized Loss	-10	-21
Corporate Notes, Certificates of Deposit and Commercial Paper	'	'
Schedule Of Available For Sale Securities [Line Items]	'	'
Less than 12 Months, Fair Value	205,690	171,894
Less than 12 Months, Unrealized Loss	-170	-93
12 Months or Greater, Fair Value	'	'
12 Months or Greater, Unrealized Loss	'	'
Total Fair Value	205,690	171,894
Total Unrealized Loss	($170)	($93)

Fair_Value_Measurements_Schedu

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) (Fair Value, Measurements, Recurring, USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets	'	'
Total	$1,953,422	$2,069,919
Agency Securities	'	'
Assets	'	'
Short-term investments	2,000	18,286
Money Market Funds	'	'
Assets	'	'
Cash equivalents	372,341	229,529
Treasury Bills	'	'
Assets	'	'
Cash equivalents	215,246	244,048
Short-term investments	100,047	265,878
Commercial Paper	'	'
Assets	'	'
Cash equivalents	142,486	194,742
Short-term investments	271,115	272,617
US Government Securities	'	'
Assets	'	'
Cash equivalents	5,006	7,545
Short-term investments	489,621	501,372
Corporate Notes	'	'
Assets	'	'
Cash equivalents	2,503	1,011
Short-term investments	277,120	255,546
Certificates of Deposit	'	'
Assets	'	'
Short-term investments	75,937	79,345
Level 1	'	'
Assets	'	'
Total	687,634	739,455
Level 1 | Agency Securities	'	'
Assets	'	'
Short-term investments	'	'
Level 1 | Money Market Funds	'	'
Assets	'	'
Cash equivalents	372,341	229,529
Level 1 | Treasury Bills	'	'
Assets	'	'
Cash equivalents	215,246	244,048
Short-term investments	100,047	265,878
Level 1 | Commercial Paper	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 1 | US Government Securities	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 1 | Corporate Notes	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 1 | Certificates of Deposit	'	'
Assets	'	'
Short-term investments	'	'
Level 2	'	'
Assets	'	'
Total	1,265,788	1,330,464
Level 2 | Agency Securities	'	'
Assets	'	'
Short-term investments	2,000	18,286
Level 2 | Money Market Funds	'	'
Assets	'	'
Cash equivalents	'	'
Level 2 | Treasury Bills	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 2 | Commercial Paper	'	'
Assets	'	'
Cash equivalents	142,486	194,742
Short-term investments	271,115	272,617
Level 2 | US Government Securities	'	'
Assets	'	'
Cash equivalents	5,006	7,545
Short-term investments	489,621	501,372
Level 2 | Corporate Notes	'	'
Assets	'	'
Cash equivalents	2,503	1,011
Short-term investments	277,120	255,546
Level 2 | Certificates of Deposit	'	'
Assets	'	'
Short-term investments	75,937	79,345
Level 3	'	'
Assets	'	'
Total	'	'
Level 3 | Agency Securities	'	'
Assets	'	'
Short-term investments	'	'
Level 3 | Money Market Funds	'	'
Assets	'	'
Cash equivalents	'	'
Level 3 | Treasury Bills	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 3 | Commercial Paper	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 3 | US Government Securities	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 3 | Corporate Notes	'	'
Assets	'	'
Cash equivalents	'	'
Short-term investments	'	'
Level 3 | Certificates of Deposit	'	'
Assets	'	'
Short-term investments	'	'

Property_and_Equipment_Net_Sch

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property and equipment, net	'	'
Property and equipment, gross	$583,265	$499,727
Less: Accumulated depreciation and amortization	-199,993	-167,065
Property and equipment, net	383,272	332,662
Equipment	'	'
Property and equipment, net	'	'
Property and equipment, gross	410,549	367,949
Furniture and Leasehold Improvements	'	'
Property and equipment, net	'	'
Property and equipment, gross	67,418	54,965
Capitalized Software	'	'
Property and equipment, net	'	'
Property and equipment, gross	56,512	47,290
Construction in Progress	'	'
Property and equipment, net	'	'
Property and equipment, gross	$48,786	$29,523

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets - Additional Information (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Finite Lived Intangible Assets [Line Items]	'	'	'
Goodwill	$363,477	'	$363,477
Amortization of intangible assets	$6,200	$3,900	'

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Finite Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value	$124,713	$124,713
Accumulated Amortization	-53,262	-47,086
Net Carrying Value	71,451	77,627
Patents and Developed Technologies	'	'
Finite Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value	100,553	100,553
Accumulated Amortization	-49,581	-45,440
Net Carrying Value	50,972	55,113
Publisher and Advertiser Relationships	'	'
Finite Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value	21,100	21,100
Accumulated Amortization	-3,006	-1,248
Net Carrying Value	18,094	19,852
Assembled Workforce	'	'
Finite Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value	1,960	1,960
Accumulated Amortization	-440	-300
Net Carrying Value	1,520	1,660
Other Intangible Assets	'	'
Finite Lived Intangible Assets [Line Items]	'	'
Gross Carrying Value	1,100	1,100
Accumulated Amortization	-235	-98
Net Carrying Value	$865	$1,002

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets - Schedule of Estimated Future Amortization Expenses (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Finite Lived Intangible Assets [Line Items]	'	'
Remainder of 2014	$15,095	'
2015	16,726	'
2016	13,421	'
2017	3,264	'
2018	3,264	'
Thereafter	19,681	'
Net Carrying Value	$71,451	$77,627

Other_Balance_Sheet_Components2

Other Balance Sheet Components - Prepaid and Other Current Assets (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Other Balance Sheet Components [Line Items]	'	'
Deferred income taxes, net	$31,382	$62,122
Prepaid and other	59,543	31,175
Total	$90,925	$93,297

Other_Balance_Sheet_Components3

Other Balance Sheet Components - Accrued and Other Current Liabilities (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Other Balance Sheet Components [Line Items]	'	'
Accrued compensation	$50,829	$29,882
Accrued equipment and maintenance	19,468	2,890
Deferred revenue	15,405	14,479
Accrued publisher payments	13,547	15,370
Accrued professional services	10,313	7,089
Accrued tax liabilities	10,073	9,515
Accrued equipment purchases under capital lease	711	2,807
Accrued other	30,938	28,278
Total	$151,284	$110,310

Net_Loss_Per_Share_Basic_and_D

Net Loss Per Share - Basic and Diluted Net Loss Per Share (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'
Net loss	($132,362)	($27,026)
Basic shares:	'	'
Weighted-average common shares outstanding	579,128	132,957
Weighted-average unvested restricted stock subject to repurchase	-8,923	-5,501
Weighted-average shares used to compute basic net loss per share	570,205	127,456
Diluted shares:	'	'
Weighted-average shares used to compute diluted net loss per share	570,205	127,456
Net loss per share attributable to common stockholders:	'	'
Basic	($0.23)	($0.21)
Diluted	($0.23)	($0.21)

Net_Loss_Per_Share_Summary_of_

Net Loss Per Share - Summary of Potential Common Shares Excluded from Calculation of Diluted Net Loss Per Share Attributable to Common Stockholders (Details)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Stock Options	'	'
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from the computation of diluted net income per share	39,796	45,465
RSUs	'	'
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from the computation of diluted net income per share	83,232	11,038
Employee Stock Purchase Plans	'	'
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from the computation of diluted net income per share	1,868	'
Shares Subject to Repurchase	'	'
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from the computation of diluted net income per share	7,898	7,486
Warrant	'	'
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]	'	'
Anti-dilutive securities excluded from the computation of diluted net income per share	117	117

Common_Stock_and_Stockholders_2

Common Stock and Stockholders' Equity - Additional Information (Details) (USD $)

3 Months Ended

3 Months Ended

1 Months Ended

3 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Feb. 28, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Restricted Common Stock

Restricted Common Stock

2013 Equity Incentive Plan

2007 Equity Incentive Plan

Pre-2013 RSUs

Pre-2013 RSUs

Employee Stock Purchase Plans

Employee Stock Option

Employee Stock Option

RSUs

RSUs

Minimum

Maximum

Restricted Common Stock

Restricted Common Stock

Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity compensation service period

'4 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'2 years

'4 years

Compensation expense related to restricted stock

'

'

'

$11,100,000

$5,200,000

'

'

'

'

'

'

'

'

'

'

'

Unamortized stock-based compensation expense related to restricted stock

'

'

'

73,400,000

'

'

'

'

'

'

'

'

126,900,000

1,200,000,000

'

'

Unamortized stock-based compensation expense, weighted average recognition period

'

'

'

'2 years 2 months 9 days

'

'

'

'

'

'7 months 17 days

'1 year 11 months 5 days

'

'2 years 5 months 12 days

'3 years 2 months 12 days

'

'

Stock options outstanding

39,796,000

'

42,246,000

'

'

13,700,000

110,000,000

'

'

'

'

'

'

'

'

'

Common stock, capital shares reserved for future issuance

'

'

'

'

'

85,200,000

'

'

'

17,700,000

'

'

'

'

'

'

Common stock, shares issued

589,298,000

'

569,922,000

'

'

'

'

'

17,100,000

'

'

'

'

'

'

'

Income taxes paid

15,140,000

'

'

'

'

'

'

15,100,000

'

'

'

'

'

'

'

'

Share-based compensation expense

'

'

'

'

'

'

'

'

'

6,200,000

'

'

'

'

'

'

Stock options exercised, intrinsic value

'

'

'

'

'

'

'

'

'

'

133,900,000

57,300,000

'

'

'

'

Stock options vested, fair value

'

'

'

'

'

'

'

'

'

'

3,500,000

3,900,000

'

'

'

'

Share-based compensation, capitalized amount

6,700,000

1,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation, weighted average grant date fair value

'

$11.13

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unamortized share-based compensation expense related to unvested stock options

'

'

'

'

'

'

'

'

'

'

28,900,000

'

'

'

'

'

Unamortized stock-based compensation expense, ESPP

'

'

'

'

'

'

'

'

'

$22,500,000

'

'

'

'

'

'

Common_Stock_and_Stockholders_3

Common Stock and Stockholders' Equity - Summary of Restricted Stock Activity (Details) (Restricted Common Stock, USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014
Restricted Common Stock	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'
Number of Unvested Shares, beginning of period	6,866
Number of Shares, Granted	'
Number of Shares, Vested	-1,498
Number of Shares, Canceled	'
Number of Unvested Shares, end of period	5,368
Weighted Average Grant Date Fair Value Per Share, beginning of period	$17.60
Weighted Average Grant Date Fair Value Per Share, Granted	'
Weighted Average Grant Date Fair Value Per Share, Vested	$16.92
Weighted Average Grant Date Fair Value Per Share, Canceled	'
Weighted Average Grant Date Fair Value Per Share, end of period	$17.79

Common_Stock_and_Stockholders_4

Common Stock and Stockholders' Equity - Summary of Stock Option Activity (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Options Outstanding - Number of Shares	'	'
Outstanding at beginning of period	42,246	'
Options granted	'	'
Options exercised	-2,282	'
Options canceled	-168	'
Outstanding at end of period	39,796	42,246
Vested and expected to vest at end of period	39,123	'
Exercisable at end of period	32,649	'
Options Outstanding - Weighted-Average Exercise Price Per Share	'	'
Outstanding at beginning of period	$1.89	'
Options granted	'	'
Options exercised	$0.59	'
Options canceled	$6.70	'
Outstanding at end of period	$1.94	$1.89
Vested and expected to vest at end of period	$1.89	'
Exercisable at end of period	$1.27	'
Options Outstanding - Weighted-Average Remaining Contractual Life	'	'
Outstanding	'6 years 2 months 16 days	'6 years 5 months 19 days
Vested and expected to vest at end of period	'6 years 2 months 9 days	'
Exercisable at end of period	'5 years 11 months 12 days	'
Options Outstanding - Aggregate Intrinsic Value	'	'
Outstanding at beginning of period	$2,609,295	'
Outstanding at end of period	1,780,127	2,609,295
Vested and expected to vest at end of period	1,752,077	'
Exercisable at end of period	$1,482,359	'

Common_Stock_and_Stockholders_5

Common Stock and Stockholders' Equity - Summary of RSU Activity (Details) (RSUs, USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014
RSUs	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'
Number of Unvested Shares, beginning of period	79,876
Shares, Granted	8,779
Shares, Vested	-4,434
Shares, Canceled	-989
Number of Unvested Shares, end of period	83,232
Shares, Vested and outstanding at end of period	2,921
Weighted Average Grant Date Fair Value Per Share, beginning of period	$19.54
Weighted Average Grant Date Fair Value Per Share, Granted	$53.84
Weighted Average Grant Date Fair Value Per Share, Vested	$16.43
Weighted Average Grant Date Fair Value Per Share, Canceled	$16.46
Weighted Average Grant Date Fair Value Per Share, end of period	$23.36
Weighted Average Grant Date Fair Value Per Share, Vested and outstanding at end of period	$16.97

Common_Stock_and_Stockholders_6

Common Stock and Stockholders' Equity - Stock Based Compensation Expense Recorded for Employee and Non Employee Stock Options (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	$126,369	$12,922
Employee	'	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	125,969	12,127
Non-Employee	'	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	$400	$795

Common_Stock_and_Stockholders_7

Common Stock and Stockholders' Equity - Compensation Expense Allocated (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	$126,369	$12,922
Cost of Revenue	'	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	9,831	484
Research and Development	'	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	78,318	8,425
Sales and Marketing	'	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	27,801	2,065
General and Administrative	'	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'	'
Stock-based compensation expense	$10,419	$1,948

Common_Stock_and_Stockholders_8

Common Stock and Stockholders' Equity - Schedule of Share-based Payment Award, Valuation Assumptions (Details) (Employee Stock Option)	3 Months Ended
	Mar. 31, 2013
Employee Stock Option	'
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]	'
Expected dividend yield	'
Risk-free interest rate	1.07%
Expected volatility	53.77%
Expected term (in years)	'5 years 7 months 17 days

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Tax Contingency [Line Items]	'	'
Income tax expense	$1,222,000	$357,000
Unrecognized tax benefits, period change	18,300,000	'
Unrecognized tax benefits, gross	61,400,000	'
RSUs | Federal	'	'
Income Tax Contingency [Line Items]	'	'
Increase of operating loss carryforwards	916,400,000	'
Excess tax benefits from the restricted stock	677,500,000	'
RSUs | State	'	'
Income Tax Contingency [Line Items]	'	'
Increase of operating loss carryforwards	241,300,000	'
Excess tax benefits from the restricted stock	$178,400,000	'

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Details) (USD $)	3 Months Ended
In Billions, unless otherwise specified	Mar. 31, 2014
Other Commitments [Line Items]	'
Unsecured revolving credit facility	$1
Line of credit facility, expiration date	22-Oct-18
Line of credit facility, interest rate description	'Loans under the credit facility bear interest, at the Companybs option, at (i) a base rate based on the highest of the prime rate, the federal funds rate plus 0.50% and an adjusted LIBOR rate for a one-month interest period plus 1.00%, in each case plus a margin ranging from 0.00% to 0.75% or (ii) an adjusted LIBOR rate plus a margin ranging from 1.00% to 1.75%.
Base Rate | Minimum	'
Other Commitments [Line Items]	'
Line of credit facility, interest rate	0.00%
Base Rate | Maximum	'
Other Commitments [Line Items]	'
Line of credit facility, interest rate	0.75%
London Interbank Offered Rate (LIBOR) | Minimum	'
Other Commitments [Line Items]	'
Line of credit facility, interest rate	1.00%
London Interbank Offered Rate (LIBOR) | Maximum	'
Other Commitments [Line Items]	'
Line of credit facility, interest rate	1.75%

Commitments_and_Contingencies_1

Commitments and Contingencies - Minimum Commitments Under Non-Cancelable Capital and Operating Lease Agreements (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Operating Leased And Capital Leased Assets [Line Items]	'	'
Remainder of 2014	$55,958	'
2015	98,691	'
2016	109,604	'
2017	109,972	'
2018	104,676	'
Thereafter	268,266	'
Total	747,167	'
Remainder of 2014	72,904	'
2015	78,520	'
2016	40,570	'
2017	12,666	'
2018	235	'
Thereafter	0	'
Total	204,895	'
Less: Amounts representing interest	12,108	'
Total capital lease obligation	192,787	'
Capital leases, short-term	90,253	87,126
Long-term portion	$102,534	$110,520

Operations_by_Geographic_Area_1

Operations by Geographic Area - Revenue by Geographic Area (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenue:	'	'
Revenue	$250,492	$114,343
United States	'	'
Revenue:	'	'
Revenue	180,039	89,416
International	'	'
Revenue:	'	'
Revenue	$70,453	$24,927

Operations_by_Geographic_Area_2

Operations by Geographic Area - Additional Information (Details)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenues From External Customers And Long Lived Assets [Line Items]	'	'
Concentration Risk, Percentage	10.00%	10.00%

Operations_by_Geographic_Area_3

Operations by Geographic Area - Long-Lived Assets by Geographic Area (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Long-lived assets:	'	'
Property and equipment, net	$383,272	$332,662
United States	'	'
Long-lived assets:	'	'
Property and equipment, net	376,271	327,250
International	'	'
Long-lived assets:	'	'
Property and equipment, net	$7,001	$5,412

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Details) (Subsequent Event, USD $)	1 Months Ended
In Millions, unless otherwise specified	8-May-14
	Acquisition
Subsequent Event	'
Subsequent Event [Line Items]	'
Number of acquisition completed	4
Stock issued during period, shares, new issues	1.6
Cash payments to acquisition	$144.20
Acquired companies' employees' stock option	0.5