Twitter (TWTR) 10-Q 3 Aug 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 27, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2
Trading Symbol	TWTR
Entity Registrant Name	TWITTER, INC.
Entity Central Index Key	1,418,091
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		737,893,225

CONSOLIDATED BALANCE SHEETS (Un

CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 1,288,323	$ 988,598
Short-term investments	2,791,589	2,785,981
Accounts receivable, net of allowance for doubtful accounts of $7,596 and $7,216 as of June 30, 2017 and December 31, 2016, respectively	524,064	650,650
Prepaid expenses and other current assets	236,126	226,967
Total current assets	4,840,102	4,652,196
Property and equipment, net	781,272	783,901
Intangible assets, net	65,291	95,334
Goodwill	1,186,189	1,185,315
Other assets	90,244	153,619
Total assets	6,963,098	6,870,365
Current liabilities:
Accounts payable	107,398	122,236
Accrued and other current liabilities	307,047	380,937
Capital leases, short-term	80,133	80,848
Total current liabilities	494,578	584,021
Convertible notes	1,582,468	1,538,967
Capital leases, long-term	83,410	66,837
Deferred and other long-term tax liabilities, net	9,247	7,556
Other long-term liabilities	64,499	68,049
Total liabilities	2,234,202	2,265,430
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.000005 par value-- 200,000 shares authorized; none issued and outstanding
Common stock, $0.000005 par value-- 5,000,000 shares authorized; 736,470 and 721,572 shares issued and outstanding as of June 30, 2017 and December 31, 2016, respectively	4	4
Additional paid-in capital	7,517,433	7,224,534
Accumulated other comprehensive loss	(46,828)	(69,253)
Accumulated deficit	(2,741,713)	(2,550,350)
Total stockholders' equity	4,728,896	4,604,935
Total liabilities and stockholders' equity	$ 6,963,098	$ 6,870,365

CONSOLIDATED BALANCE SHEETS (U3

CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 7,596	$ 7,216
Preferred stock, par value	$ 0.000005	$ 0.000005
Preferred stock, shares authorized	200,000,000	200,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.000005	$ 0.000005
Common stock, shares authorized	5,000,000,000	5,000,000,000
Common stock, shares issued	736,470,000	721,572,000
Common stock, shares outstanding	736,470,000	721,572,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Revenue	$ 573,855	$ 601,958	$ 1,122,106	$ 1,196,479
Costs and expenses
Cost of revenue	212,908	202,966	433,247	401,371
Research and development	143,171	178,511	271,899	334,305
Sales and marketing	185,296	236,619	354,890	472,790
General and administrative	70,839	70,238	140,707	133,505
Total costs and expenses	612,214	688,334	1,200,743	1,341,971
Loss from operations	(38,359)	(86,376)	(78,637)	(145,492)
Interest expense	(26,396)	(24,934)	(51,805)	(49,827)
Other income (expense), net	(48,320)	6,734	(40,998)	13,040
Loss before income taxes	(113,075)	(104,576)	(171,440)	(182,279)
Provision for income taxes	3,413	2,641	6,607	4,669
Net loss	$ (116,488)	$ (107,217)	$ (178,047)	$ (186,948)
Net loss per share attributable to common stockholders:
Basic	$ (0.16)	$ (0.15)	$ (0.25)	$ (0.27)
Diluted	$ (0.16)	$ (0.15)	$ (0.25)	$ (0.27)
Weighted-average shares used to compute net loss per share attributable to common stockholders:
Basic	730,069	698,326	726,083	694,959
Diluted	730,069	698,326	726,083	694,959

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (116,488)	$ (107,217)	$ (178,047)	$ (186,948)
Other comprehensive income (loss), net of tax:
Change in unrealized gain (loss) on investments in available-for-sale securities	69	(961)	(160)	3,481
Change in foreign currency translation adjustment	14,462	(13,052)	22,585	(2,418)
Net change in accumulated other comprehensive loss	14,531	(14,013)	22,425	1,063
Comprehensive loss	$ (101,957)	$ (121,230)	$ (155,622)	$ (185,885)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities
Net loss	$ (178,047,000)	$ (186,948,000)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization expense	205,855,000	181,904,000
Stock-based compensation expense	230,393,000	318,611,000
Amortization of discount on convertible notes	39,289,000	36,940,000
Changes in bad debt provision	1,355,000	2,573,000
Deferred income taxes	(768,000)	45,000
Impairment of investments in privately-held companies	55,000,000	0
Other adjustments	(4,854,000)	5,268,000
Changes in assets and liabilities, net of assets acquired and liabilities assumed from acquisitions:
Accounts receivable	133,026,000	86,213,000
Prepaid expenses and other assets	(1,656,000)	(16,985,000)
Accounts payable	(13,616,000)	(37,085,000)
Accrued and other liabilities	(72,822,000)	(13,216,000)
Net cash provided by operating activities	393,155,000	377,320,000
Cash flows from investing activities
Purchases of property and equipment	(83,217,000)	(98,235,000)
Purchases of marketable securities	(1,578,045,000)	(1,330,946,000)
Proceeds from maturities of marketable securities	1,461,687,000	1,232,249,000
Proceeds from sales of marketable securities	108,817,000	42,416,000
Proceeds from sales of long-lived assets	35,000,000
Changes in restricted cash	3,221,000	(590,000)
Purchases of investments in privately-held companies	(525,000)	(78,002,000)
Business combinations, net of cash acquired		(80,142,000)
Other investing activities	(10,006,000)	(81,000)
Net cash used in investing activities	(63,068,000)	(313,331,000)
Cash flows from financing activities
Taxes paid related to net share settlement of equity awards	(5,023,000)	(6,994,000)
Payments of capital lease obligations	(55,150,000)	(48,740,000)
Proceeds from exercise of stock options	7,331,000	6,208,000
Proceeds from issuances of common stock under employee stock purchase plan	14,019,000	15,821,000
Other financing activities		22,000
Net cash used in financing activities	(38,823,000)	(33,683,000)
Net increase in cash and cash equivalents	291,264,000	30,306,000
Foreign exchange effect on cash and cash equivalents	8,461,000	5,933,000
Cash and cash equivalents at beginning of period	988,598,000	911,471,000
Cash and cash equivalents at end of period	1,288,323,000	947,710,000
Supplemental disclosures of non-cash investing and financing activities
Common stock issued in connection with acquisitions		644,000
Equipment purchases under capital leases	70,926,000	25,922,000
Changes in accrued property and equipment purchases	$ (1,847,000)	$ 10,938,000

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
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 offers products and services for users, advertisers, developers and platform and data partners. 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 (“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, 2016. Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with 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 Recently adopted accounting pronouncements In March 2016, the Financial Accounting Standards Board (“FASB”) issued a new accounting standard update on simplifying the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new guidance also allows an entity to account for forfeitures when they occur. This guidance became effective for reporting periods beginning after December 15, 2016. The Company adopted this new guidance on January 1, 2017. Upon adoption, tax benefits in excess of stock-based compensation costs, and tax deficiencies, are recorded in the consolidated statements of operations as a component of the provision for income taxes, whereas they previously were recorded in equity. The previously unrecognized excess tax benefits as of December 31, 2016 were recorded as an increase to deferred tax assets. However, given the valuation allowance placed on substantially all of the Company’s deferred tax assets, the recognition upon adoption did not have an impact on the Company’s accumulated deficit. As a result of adopting the new standard utilizing the modified retrospective approach, the Company’s deferred tax assets increased by approximately $0.93 billion with a corresponding increase in its valuation allowance. The Company also elected to account for forfeitures as they occur, rather than estimate expected forfeitures. The adoption of this new guidance resulted in a net cumulative-effect adjustment of $13.3 million increase to accumulated deficit as of January 1, 2017, related to the accounting of forfeitures using the modified retrospective method. Additionally, the Company adopted the aspects of the guidance affecting the cash flow presentation retrospectively, which resulted in an immaterial reclassification of excess tax benefits from financing activities to operating activities in the Company’s consolidated statements of cash flows. In January 2017, the FASB issued a new accounting standard update on simplifying the accounting for goodwill impairment. The new guidance eliminates the requirement to calculate the implied fair value of goodwill (i.e., Step 2 of the goodwill impairment test) to measure a goodwill impairment charge. Instead, entities will record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value. The Company adopted this guidance prospectively during the three months ended March 31, 2017 and the adoption had no impact on the Company’s financial statements. In May 2017, the FASB issued a new accounting standard update on clarifying when changes to share-based payment awards must be accounted for as modifications. According to the new guidance, entities will apply the modification accounting guidance if the value, vesting conditions or classification of the award changes. The Company adopted this guidance prospectively during the three months ended June 30, 2017 and the adoption had no impact on the Company’s financial statements. Recently issued accounting pronouncements not yet adopted In May 2014, the FASB issued a new accounting standard update on revenue recognition from contracts with customers. The new guidance will replace all current GAAP guidance on this topic and eliminate industry-specific guidance. According to the new guidance, revenue is recognized when promised goods or services are transferred to customers in an amount that reflects the consideration for which the Company expects to be entitled in exchange for those goods or services. The guidance will be effective for fiscal years, and interim periods with those fiscal years, beginning after December 15, 2017 and can be applied either retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. In March 2016, April 2016, May 2016 and December 2016, the FASB further amended the guidance to clarify the implementation on principal versus agent considerations, the identification of performance obligation and the licensing implementation guidance to provide narrow-scope improvements and practical expedients, and technical corrections and improvements. The Company will adopt this standard effective January 1, 2018 and currently anticipates adopting the standard using the modified retrospective method. The Company is still in the process of completing its analysis of the impact this standard will have on the consolidated financial statements including its disclosure. Specifically, while the Company has not yet finalized its analysis of the recognition impact this standard will have on advertising revenue, the Company does not expect the impact to be material; the Company is still assessing the recognition impact of adopting this standard on data licensing and other revenue; and the Company has not completed its assessment of the presentation impact of adoption of the new principal versus agent guidance on its arrangements. As part of the Company’s assessment and implementation plan, the Company is evaluating and implementing changes to its policies, procedures and controls. In March 2017, the FASB issued a new accounting standard update on shortening the premium amortization period for purchased non-contingently callable debt securities. The new guidance shortens the amortization period for the premium on purchased non-contingently callable debt securities to the earliest call date. Currently, entities generally amortize the premium as a yield adjustment over the contractual life of the security. This guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. Early adoption is permitted. The Company is evaluating the impact of adopting this new accounting standard update on the financial statements and related disclosures. With the exception of the standards discussed above, there have been no other recent accounting pronouncements or changes in accounting pronouncements during the six months ended June 30, 2017, as compared to the recent accounting pronouncements described in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016, that are of significance or potential significance to the Company.

Cash, Cash Equivalents and Shor

Cash, Cash Equivalents and Short-term Investments	6 Months Ended
	Jun. 30, 2017
Cash And Cash Equivalents [Abstract]
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): June 30, December 31, 2017 2016 Cash and cash equivalents: Cash $ 251,554 $ 253,808 Money market funds 642,605 422,515 U.S. government and agency securities including treasury bills 27,899 12,639 Corporate notes, commercial paper and certificates of deposit 366,265 299,636 Total cash and cash equivalents $ 1,288,323 $ 988,598 Short-term investments: U.S. government and agency securities including treasury bills $ 1,146,379 $ 1,183,768 Corporate notes, commercial paper and certificates of deposit 1,645,210 1,602,213 Total short-term investments $ 2,791,589 $ 2,785,981 The contractual maturities of securities classified as available-for-sale as of June 30, 2017 were as follows (in thousands): June 30, 2017 Due within one year $ 1,969,093 Due after one year through two years 822,496 Total $ 2,791,589 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): June 30, 2017 Gross Gross Gross Aggregated Amortized Unrealized Unrealized Estimated Costs Gains Losses Fair Value U.S. government and agency securities including treasury bills $ 1,148,568 $ 157 $ (2,346 ) $ 1,146,379 Corporate notes, commercial paper and certificates of deposit 1,645,451 275 (516 ) 1,645,210 Total available-for-sale securities classified as short-term investments $ 2,794,019 $ 432 $ (2,862 ) $ 2,791,589 December 31, 2016 Gross Gross Gross Aggregated Amortized Unrealized Unrealized Estimated Costs Gains Losses Fair Value U.S. government and agency securities including treasury bills $ 1,185,274 $ 136 $ (1,642 ) $ 1,183,768 Corporate notes, commercial paper and certificates of deposit 1,603,048 114 (949 ) 1,602,213 Total available-for-sale securities classified as short-term investments $ 2,788,322 $ 250 $ (2,591 ) $ 2,785,981 There were no securities in a continuous loss position for 12 months or longer as of June 30, 2017. The gross unrealized loss on securities in a continuous loss position for 12 months or longer was not material as of December 31, 2016. 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	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 3. Fair Value Measurements The Company measures its cash equivalents, short-term investments and derivative financial instruments at fair value. The Company classifies its cash equivalents, short-term investments and derivative financial instruments within Level 1 or Level 2 because the Company values these investments using quoted market prices or alternative pricing sources and models utilizing market observable inputs. The fair value of the Company’s Level 1 financial assets is based on quoted market prices of the identical underlying security. The fair value of the Company’s Level 2 financial assets is based on inputs that are directly or indirectly observable in the market, including the readily-available pricing sources for the identical underlying security that may not be actively traded. 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 June 30, 2017 and December 31, 2016 based on the three-tier fair value hierarchy (in thousands): June 30, 2017 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 642,605 $ — $ — $ 642,605 Treasury bills 27,899 — — 27,899 Corporate notes — 768 — 768 Commercial paper — 362,485 — 362,485 Certificates of deposit — 3,012 — 3,012 Short-term investments: U.S. government securities — 733,924 — 733,924 Agency securities — 412,455 — 412,455 Corporate notes — 752,793 — 752,793 Commercial paper — 263,409 — 263,409 Certificates of deposit — 629,008 — 629,008 Other current assets: Foreign currency contracts — 2,966 — 2,966 Total $ 670,504 $ 3,160,820 $ — $ 3,831,324 Liabilities Other current liabilities: Foreign currency contracts — 1,472 — 1,472 Total $ — $ 1,472 $ — $ 1,472 December 31, 2016 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 422,515 $ — $ — $ 422,515 Treasury bills 12,639 — — 12,639 Corporate notes — 7,387 — 7,387 Commercial paper — 292,249 — 292,249 Short-term investments: U.S. government securities — 657,502 — 657,502 Agency securities — 526,266 — 526,266 Corporate notes — 689,986 — 689,986 Commercial paper — 311,238 — 311,238 Certificates of deposit — 600,989 — 600,989 Other current assets: Foreign currency contracts — 1,955 — 1,955 Total $ 435,154 $ 3,087,572 $ — $ 3,522,726 Liabilities Other current liabilities: Foreign currency contracts — 500 — 500 Total $ — $ 500 $ — $ 500 In 2014, the Company issued $935.0 million principal amount of 0.25% convertible senior notes due in 2019 (the “2019 Notes”) and $954.0 million principal amount of 1.00% convertible senior notes due in 2021 (the “2021 Notes” and together with the 2019 Notes, the “Notes”) in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended. Refer to Note 8 – Convertible Senior Notes for further details on the Notes. The estimated fair value of the 2019 Notes and 2021 Notes based on a market approach as of June 30, 2017 was approximately $882.6 million and $872.1 million respectively, which represents a Level 2 valuation. The estimated fair value was determined based on the estimated or actual bids and offers of the Notes in an over-the-counter market on the last business day of the period. Derivative Financial Instruments The Company enters into foreign currency forward contracts with financial institutions to reduce the risk that its earnings may be adversely affected by the impact of exchange rate fluctuations on monetary assets or liabilities denominated in currencies other than the functional currency of a subsidiary. These contracts do not subject the Company to material balance sheet risk due to exchange rate movements because gains and losses on these derivatives are intended to offset gains and losses on the hedged foreign currency denominated assets and liabilities. These foreign currency forward contracts are not designated as hedging instruments. The Company recognizes these derivative instruments as either assets or liabilities in the consolidated balance sheets at fair value based on a Level 2 valuation. The Company records changes in the fair value (i.e., gains or losses) of the derivatives as other income (expense), net in the consolidated statements of operations. The notional principal of foreign currency contracts outstanding was equivalent to $553.6 million and $536.9 million at June 30, 2017 and December 31, 2016, respectively. The fair values of outstanding derivative instruments for the periods presented on a gross basis are as follows (in thousands): June 30, December 31, Balance Sheet Location 2017 2016 Assets Foreign currency contracts not designated as hedging instruments Other current assets $ 2,966 $ 1,955 Liabilities Foreign currency contracts not designated as hedging instruments Other current liabilities $ 1,472 $ 500 The Company recognized $5.6 million and $2.4 million of net gains on the foreign currency contracts in the three and six months ended June 30, 2017, respectively. The Company recognized $6.5 million and $4.7 million of net losses on the foreign currency contracts in the three and six months ended June 30, 2016, respectively.

Property and Equipment, Net

Property and Equipment, Net	6 Months Ended
	Jun. 30, 2017
Property Plant And Equipment [Abstract]
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): June 30, December 31, 2017 2016 Property and equipment, net Equipment $ 990,795 $ 909,797 Furniture and leasehold improvements 319,414 304,613 Capitalized software 398,983 353,163 Construction in progress 71,694 74,255 Total 1,780,886 1,641,828 Less: Accumulated depreciation and amortization (999,614 ) (857,927 ) Property and equipment, net $ 781,272 $ 783,901

Goodwill and Intangible Assets

Goodwill and Intangible Assets	6 Months Ended
	Jun. 30, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Note 5. Goodwill and Intangible Assets The following table presents the goodwill activities for the periods presented (in thousands): Goodwill Balance as of December 31, 2016 $ 1,185,315 Foreign currency translation adjustment and other 874 Balance as of June 30, 2017 $ 1,186,189 For each of the periods presented, gross goodwill balance equaled the net balance since no impairment charges have been recorded. The following table presents the detail of intangible assets for the periods presented (in thousands): Gross Carrying Accumulated Net Carrying Value Amortization Value June 30, 2017: Patents and developed technologies $ 123,324 $ (63,434 ) $ 59,890 Publisher and advertiser relationships 53,100 (47,699 ) 5,401 Total $ 176,424 $ (111,133 ) $ 65,291 December 31, 2016: Patents and developed technologies $ 122,611 $ (47,160 ) $ 75,451 Publisher and advertiser relationships 53,100 (33,217 ) 19,883 Total $ 175,711 $ (80,377 ) $ 95,334 Amortization expense associated with intangible assets for the three months ended June 30, 2017 and 2016 was $14.3 million and $12.8 million, respectively, and for the six months ended June 30, 2017 and 2016 was $30.5 million and $25.5 million, respectively. Estimated future amortization expense as of June 30, 2017 is as follows (in thousands): Remainder of 2017 $ 15,830 2018 16,023 2019 8,496 2020 6,222 2021 5,826 Thereafter 12,894 Total $ 65,291

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	6 Months Ended
	Jun. 30, 2017
Payables And Accruals [Abstract]
Accrued and Other Current Liabilities	Note 6. Accrued and Other Current Liabilities The following table presents the detail of accrued and other current liabilities for the periods presented (in thousands): June 30, December 31, 2017 2016 Accrued compensation $ 73,833 $ 82,354 Accrued restructuring 43,937 55,942 Accrued publisher, content and ad network costs 21,816 44,362 Deferred revenue 22,700 33,659 Accrued tax liabilities 30,945 29,558 Accrued fixed assets and maintenance 25,214 25,265 Accrued other 88,602 109,797 Total $ 307,047 $ 380,937

Investments in Privately-Held C

Investments in Privately-Held Companies	6 Months Ended
	Jun. 30, 2017
Investments All Other Investments [Abstract]
Investments in Privately-Held Companies	Note 7. Investments in Privately-Held Companies The Company makes strategic investments in privately-held companies and assesses the accounting for these investments under the equity or cost method. The Company also evaluates each investee to determine if the investee is a variable interest entity and, if so, whether the Company is the primary beneficiary of the variable interest entity. The Company has determined, as of June 30, 2017, there were no variable interest entities required to be consolidated in the Company’s consolidated financial statements. The Company’s investments in privately-held companies are primarily accounted for using the cost method which had a carrying value of $35.2 million and $90.2 million as of June 30, 2017 and December 31, 2016, respectively. The maximum loss the Company can incur for its investments is their carrying value. These investments in privately-held companies are included within Other Assets on the consolidated balance sheets. The Company periodically evaluates the carrying value of the cost-method investments, when events and circumstances indicate that the carrying amount of the investment may not be recovered. The Company estimates the fair value of the cost-method investments to assess whether impairment losses shall be recorded using Level 3 inputs. These investments include the Company’s holdings in privately-held companies that are not exchange traded and therefore not supported with observable market prices hence the Company may determine the fair value by reviewing equity valuation reports, current financial results, long-term plans of the private company, the amount of cash that the private company has on-hand, the ability to obtain additional financing and overall market conditions in which the private company operates. In the three months ended June 30, 2017, the Company determined that the estimated fair value of a cost-method investment, valued using Level 3 inputs, was below its carrying value and that the carrying value of this investment was not expected to be recoverable within a reasonable period of time. The Company calculated the expected value of the cost-method investment based on third-party offers received by the investee and the Company’s expectation of its negotiated investment value based on the amount of cash that the investee has on-hand, the investee’s ability to obtain additional financing and overall market conditions in which the investee operates. Based on this analysis, the Company recorded a $55.0 million other-than-temporary impairment charge during the three months ended June 30, 2017, which was recorded within other income (expense), net in the consolidated statements of operations. No impairment charges have been recorded in the three months ended March 31, 2017, and three and six months ended June 30, 2016.

Convertible Senior Notes

Convertible Senior Notes	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Convertible Senior Notes	Note 8. Convertible Senior Notes In 2014, the Company issued $935.0 million principal amount of 2019 Notes and $954.0 million principal amount of 2021 Notes. The total net proceeds from this offering were approximately $1.86 billion, after deducting $28.3 million of initial purchasers’ discount and $0.5 million debt issuance costs in connection with the 2019 Notes and the 2021 Notes. The June 30, 2017 June 30, 2017 The Notes consisted of the following (in thousands): June 30, 2017 December 31, 2016 2019 Notes 2021 Notes 2019 Notes 2021 Notes Principal amounts: Principal $ 935,000 $ 954,000 $ 935,000 $ 954,000 Unamortized initial purchasers' discount and debt discount (1) (112,758 ) (193,774 ) (136,376 ) (213,657 ) Net carrying amount $ 822,242 $ 760,226 $ 798,624 $ 740,343 Carrying amount of the equity component (2) $ 222,826 $ 283,283 $ 222,826 $ 283,283 (1) (2) As of June 30, 2017, the remaining life of the 2019 Notes and 2021 Notes is approximately 26 months and 50 months, respectively.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Net Loss Per Share	Note 9. Net Loss per Share Basic net loss per share is computed by dividing total net loss attributable to common stockholders by the weighted-average common shares outstanding during the period. 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, during the period, including potential dilutive common stock instruments. In the three and six months ended June 30, 2017 and 2016, the Company’s potential common stock instruments such as stock options, restricted stock units (“RSUs”), shares to be purchased under the 2013 Employee Stock Purchase Plan (“ESPP”), shares subject to repurchases, conversion feature of the Notes and the warrants 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 June 30, Six Months Ended June 30, 2017 2016 2017 2016 Net loss $ (116,488 ) $ (107,217 ) $ (178,047 ) $ (186,948 ) Basic shares: Weighted-average common shares outstanding 734,178 704,174 730,348 700,920 Weighted-average restricted stock subject to repurchase (4,109 ) (5,848 ) (4,265 ) (5,961 ) Weighted-average shares used to compute basic net loss per share 730,069 698,326 726,083 694,959 Diluted shares: Weighted-average shares used to compute diluted net loss per share 730,069 698,326 726,083 694,959 Net loss per share attributable to common stockholders: Basic $ (0.16 ) $ (0.15 ) $ (0.25 ) $ (0.27 ) Diluted $ (0.16 ) $ (0.15 ) $ (0.25 ) $ (0.27 ) The following number of potential common shares at the end of each period 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 and Six Months Ended June 30, 2017 2016 RSUs 37,979 58,806 Warrants 24,329 24,329 Stock options 5,301 9,340 Shares subject to repurchase and others 6,410 10,457 Since the Company expects to settle the principal amount of the outstanding Notes in cash, the Company uses the treasury stock method for calculating any potential dilutive effect of the conversion spread on diluted net income per share, if applicable. The conversion spread of 24.3 million shares will have a dilutive impact on diluted net income per share of common stock when the average market price of the Company’s common stock for a given period exceeds the conversion price of $77.64 per share for the Notes. If the average market price of the common stock exceeds the exercise price of the warrants, $105.28, the warrants will have a dilutive effect on the earnings per share assuming that the Company is profitable. Since the average market price of the common stock is below $105.28, the warrants are anti-dilutive.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2017
Stockholders Equity Note [Abstract]
Stockholders' Equity	Note 10. Stockholders’ Equity Equity Incentive Plans The Company’s 2013 Equity Incentive Plan became effective upon the completion of the Company’s initial public offering and serves as the successor to the 2007 Equity Incentive Plan. Initially, 68.3 million shares were reserved under the 2013 Equity Incentive Plan and any shares subject to options or other similar awards granted under the 2007 Equity Incentive Plan that expire, are forfeited, are repurchased by the Company or otherwise terminate unexercised will become available under the 2013 Equity Incentive Plan. The number of shares of the Company’s common stock available for issuance under the 2013 Equity Incentive Plan were and will be increased on the first day of each fiscal year beginning with the 2014 fiscal year, in an amount equal to the least of (i) 60,000,000 shares, (ii) 5% of the outstanding shares on the last day of the immediately preceding fiscal year or (iii) such number of shares determined by the Company’s Board of Directors. No additional shares have been issued under the 2007 Equity Incentive Plan since 2013. Employee Stock Purchase Plan The number of shares available for sale under the ESPP were and will be increased on the first day of each fiscal year beginning with the 2014 fiscal year, in an amount equal to the least of i) 11.3 million shares; ii) 1% of the outstanding shares of the Company’s common stock as of the last day of the immediately preceding fiscal year; or iii) such other amount as determined by the Company’s Board of Directors. During the six months ended June 30, 2017, employees purchased an aggregate of 1.1 million shares under the ESPP at a weighted-average price of $12.43 per share. During the six months ended June 30, 2016, employees purchased an aggregate of 1.3 million shares under the ESPP at a price of $11.99 per share. During the three months ended June 30, 2017 and 2016, the Company recorded $1.8 million and $5.7 million, respectively, and recorded $4.4 million and $11.4 million during the six months ended June 30, 2017 and 2016, respectively, of stock-based compensation expense related to the ESPP. Restricted Common Stock The Company has granted restricted common stock to certain 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 up to four years from the issuance date, and the Company has the right 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 six months ended June 30, 2017 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, 2016 5,097 $ 23.04 Vested (1,166 ) $ 23.76 Canceled (441 ) $ 38.03 Unvested restricted common stock at June 30, 2017 3,490 $ 20.90 Stock Option Activity A summary of stock option activity for the six months ended June 30, 2017 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, 2016 8,723 $ 7.71 $ 4.25 $ 98,240 Options exercised (3,239 ) $ 2.26 Options canceled (183 ) $ 2.72 Outstanding at June 30, 2017 5,301 $ 11.20 5.17 $ 56,414 Exercisable at June 30, 2017 4,192 $ 8.73 4.42 $ 49,988 The total intrinsic values of stock options exercised during the three months ended June 30, 2017 and 2016 were $6.7 million and $12.4 million, respectively, and $44.1 million and $32.2 million during the six months ended June 30, 2017 and 2016, respectively. Performance Restricted Stock Units Activity The Company grants restricted stock units to certain of its executive officers periodically that vest based on the Company’s attainment of the annual financial performance goals and the executives’ continued employment through the vesting date, approximately one year (“PRSUs”). These PRSUs are granted when the annual performance targets are set by the Compensation Committee of the Board of Directors, generally in the first quarter of each financial year. During the six months ended June 30, 2017, the Company granted 318,400 PRSUs, at the 100% target level, for the 2017 performance goals with a weighted-average grant date fair value of $15.28 per share. During the year ended December 31, 2016, the Company granted 165,833 PRSUs, at the 100% target level, of which 117,808 vested in 2017. The Company also grants restricted stock units to certain of its executive officers that vest based on Twitter stock price performance relative to a broad-market index over a two year period from the grant date and the executives continued employment through the vesting date (“TSR RSUs”). During the six months ended June 30, 2017, the Company granted 134,400 TSR RSUs with a weighted-average grant date fair value of $13.02 per share. In addition, there are 1,408,533 additional PRSUs and TSR RSUs that will vest based on performance goals and Total Shareholder Return (“TSR”) targets in 2018 to 2020, if achieved, at target levels. Since the performance and TSR targets for those additional awards have not been established, they are not considered granted nor are they presented as outstanding. RSU Activity The following table summarizes the activity related to the Company’s RSUs, excluding PRSUs, for the six months ended June 30, 2017. 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, 2016 48,069 $ 22.64 Granted 9,111 $ 15.23 Vested (11,138 ) $ 22.29 Canceled (8,063 ) $ 22.61 Unvested and outstanding at June 30, 2017 37,979 $ 20.97 The total fair value of RSUs vested during the three months ended June 30, 2017 and 2016 was $86.1 million and $119.8 million, respectively, and $187.0 million and $212.4 million during the six months ended June 30, 2017 and 2016, respectively. Stock-Based Compensation Expense Stock-based compensation expense is allocated based on the cost center to which the award holder belongs. Total stock-based compensation expense by function is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Cost of revenue $ 6,253 $ 7,858 $ 12,205 $ 15,826 Research and development 63,625 90,916 128,011 166,495 Sales and marketing 20,694 45,856 45,783 91,957 General and administrative 22,824 23,065 44,394 44,333 Total stock-based compensation expense $ 113,396 $ 167,695 $ 230,393 $ 318,611 The Company capitalized $14.2 million and $17.9 million of stock-based compensation expense associated with the cost for developing software for internal use in the three months ended June 30, 2017 and 2016, respectively, and $30.3 million and $40.5 million in the six months ended June 30, 2017 and 2016, respectively. As of June 30, 2017, there was $738.2 million of gross unamortized stock-based compensation expense related to unvested awards which will be recognized, net of actual forfeiture in the future, over a weighted-average period of 2.3 years. Upon adoption of the stock-based compensation expense simplification rule as of January 1, 2017, the Company no longer applies a forfeiture rate to determine the unamortized stock-based compensation expense; instead, the Company accounts for forfeitures as they occur.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Note 11. 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 a Federal income tax examination by the Internal Revenue Service (IRS) for tax years 2011, 2012 and 2013. 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 an income tax provision of $3.4 million and $2.6 million for the three months ended June 30, 2017 and 2016, respectively, and an income tax provision of $6.6 million and $4.7 million for the six months ended June 30, 2017 and 2016, respectively. As of June 30, 2017, 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 six months ended June 30, 2017 will not be realized by the end of the 2017 fiscal year. Accordingly, the Company did not record the tax benefits of the U.S. losses incurred during the six months ended June 30, 2017. 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 and six months ended June 30, 2017, the amount of gross unrecognized tax benefits increased by $12.8 million and $23.5 million, respectively. As of June 30, 2017, the Company has $293.0 million of unrecognized tax benefits, including $286.0 million of unrecognized tax benefits which, if recognized, will not affect the annual effective tax rate as these unrecognized tax benefits would increase deferred tax assets which would be subject to a full valuation allowance, while the remaining $7.0 million of unrecognized tax benefits which, if recognized, would affect the annual effective tax rate.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2017
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 12. Commitments and Contingencies Credit Facility The Company has a revolving credit agreement with certain lenders, which provides for a $1.0 billion revolving unsecured credit facility maturing on October 22, 2018. The Company is obligated to pay interest on loans under the credit facility and 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. In addition, the credit facility contains restrictions on payments including cash payments of dividends. As of June 30, 2017, no amounts had been drawn under the credit facility. Leases The Company has entered into various non-cancelable operating lease agreements for certain offices and data center facilities with contractual lease periods expiring through 2028. Under the terms of certain leases, the Company is committed to pay for certain taxes, insurance, maintenance and management expenses. Certain of these arrangements have free rent periods or escalating rent payment provisions, and the Company recognizes rent expense under such arrangements on a straight-line basis. There were no material changes in the Company’s leases compared to the disclosure in its Annual Report on Form 10-K for the fiscal year ended December 31, 2016. Legal Proceedings The Company is currently involved in, and will likely in the future be involved in, legal proceedings, claims and government investigations in the normal course of business. These proceedings, in the form of both individual and class action litigation, have included, but are not limited to matters involving intellectual property, defamation, privacy, securities, employment and contractual rights. 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 June 30, 2017 and December 31, 2016, there was no litigation or contingency with at least a reasonable possibility of a material loss. No material losses have been recorded during the three and six months ended June 30, 2017 and 2016 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 June 30, 2017 and December 31, 2016.

Operations by Geographic Area

Operations by Geographic Area	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Operations by Geographic Area	Note 13. Operations by Geographic Area Revenue Revenue by geography is based on the billing addresses of the customers. The following table sets forth revenue by services and revenue by geographic area (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Revenue by services: Advertising services $ 489,148 $ 534,524 $ 962,928 $ 1,065,265 Data licensing and other 84,707 67,434 159,178 131,214 Total revenue $ 573,855 $ 601,958 $ 1,122,106 $ 1,196,479 Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Revenue by geographic area: United States $ 334,675 $ 360,676 $ 675,259 $ 750,943 International 239,180 241,282 446,847 445,536 Total revenue $ 573,855 $ 601,958 $ 1,122,106 $ 1,196,479 Japan accounted for $74.2 million and $61.2 million, or 13% and 10% of total revenue for the three months ended June 30, 2017 and 2016, respectively, and also for $146.8 million, or 13% of total revenue for the six months ended June 30, 2017. No individual country from the international markets contributed in excess of 10% of the total revenue for the six months ended June 30, 2016. Property and Equipment, net The following table sets forth property and equipment, net by geographic area (in thousands): June 30, December 31, 2017 2016 Property and equipment, net: United States $ 730,269 $ 728,429 International 51,003 55,472 Total property and equipment, net $ 781,272 $ 783,901

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2017
Related Party Transactions [Abstract]
Related Party Transactions	Note 14. Related Party Transactions The Company has a partnership agreement for no consideration with Square, Inc., for which Jack Dorsey (the Company’s Chief Executive Officer) serves as Chief Executive Officer, to enable U.S. political donations through Tweets. Neither Square, Inc. nor the Company will pay each other any amounts in connection with the agreement. The agreement has no impact on the Company’s financial statements.

Restructuring Charges

Restructuring Charges	6 Months Ended
	Jun. 30, 2017
Restructuring And Related Activities [Abstract]
Restructuring Charges	Note 15. Restructuring Charges On October 25, 2016, the Board of Directors of the Company approved a reduction in force plan (“2016 Plan”) of up to approximately 9% of the Company’s positions globally. The reduction in force was undertaken to eliminate investment in noncore areas and drive toward greater efficiency, while allowing the Company to continue to invest in its highest priorities. The Company expects the reduction in force to be completed in 2017. On December 17, 2016, the Board of Directors of the Company approved a lease abandonment plan (“2016 Lease Plan”) to abandon excess office space with lease terms expiring through 2028. The following table summarizes the activities related to restructuring charges, as discussed above (in thousands): 2016 Employee 2016 Termination Plan Lease Plan Charges $ 21,611 $ 79,685 Cash payment (11,629 ) (3,562 ) Non-cash and other adjustments (6,357 ) (19,577 ) Accrued as of December 31, 2016 $ 3,625 $ 56,546 Charges (1) $ 788 $ 1,539 Cash payment (4,240 ) (11,319 ) Non-cash and other adjustments 108 14 Accrued as of June 30, 2017 $ 281 $ 46,780 Reflected in consolidated balance sheets as of June 30, 2017: Accrued and other current liabilities $ 281 $ 43,656 Other long-term liabilities $ — $ 3,124 (1) recorded a reduction to restructuring charges of $0.2 million within sales and marketing in the consolidated statements of operations. recorded restructuring charges of $1.3 million within sales and marketing, $0.6 million within research and development, $0.3 million within general and administrative and $0.1 million within cost of revenue in the consolidated statements of operations.

Description of Business and S22

Description of Business and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
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 (“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, 2016.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with 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 Recently adopted accounting pronouncements In March 2016, the Financial Accounting Standards Board (“FASB”) issued a new accounting standard update on simplifying the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new guidance also allows an entity to account for forfeitures when they occur. This guidance became effective for reporting periods beginning after December 15, 2016. The Company adopted this new guidance on January 1, 2017. Upon adoption, tax benefits in excess of stock-based compensation costs, and tax deficiencies, are recorded in the consolidated statements of operations as a component of the provision for income taxes, whereas they previously were recorded in equity. The previously unrecognized excess tax benefits as of December 31, 2016 were recorded as an increase to deferred tax assets. However, given the valuation allowance placed on substantially all of the Company’s deferred tax assets, the recognition upon adoption did not have an impact on the Company’s accumulated deficit. As a result of adopting the new standard utilizing the modified retrospective approach, the Company’s deferred tax assets increased by approximately $0.93 billion with a corresponding increase in its valuation allowance. The Company also elected to account for forfeitures as they occur, rather than estimate expected forfeitures. The adoption of this new guidance resulted in a net cumulative-effect adjustment of $13.3 million increase to accumulated deficit as of January 1, 2017, related to the accounting of forfeitures using the modified retrospective method. Additionally, the Company adopted the aspects of the guidance affecting the cash flow presentation retrospectively, which resulted in an immaterial reclassification of excess tax benefits from financing activities to operating activities in the Company’s consolidated statements of cash flows. In January 2017, the FASB issued a new accounting standard update on simplifying the accounting for goodwill impairment. The new guidance eliminates the requirement to calculate the implied fair value of goodwill (i.e., Step 2 of the goodwill impairment test) to measure a goodwill impairment charge. Instead, entities will record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value. The Company adopted this guidance prospectively during the three months ended March 31, 2017 and the adoption had no impact on the Company’s financial statements. In May 2017, the FASB issued a new accounting standard update on clarifying when changes to share-based payment awards must be accounted for as modifications. According to the new guidance, entities will apply the modification accounting guidance if the value, vesting conditions or classification of the award changes. The Company adopted this guidance prospectively during the three months ended June 30, 2017 and the adoption had no impact on the Company’s financial statements. Recently issued accounting pronouncements not yet adopted In May 2014, the FASB issued a new accounting standard update on revenue recognition from contracts with customers. The new guidance will replace all current GAAP guidance on this topic and eliminate industry-specific guidance. According to the new guidance, revenue is recognized when promised goods or services are transferred to customers in an amount that reflects the consideration for which the Company expects to be entitled in exchange for those goods or services. The guidance will be effective for fiscal years, and interim periods with those fiscal years, beginning after December 15, 2017 and can be applied either retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. In March 2016, April 2016, May 2016 and December 2016, the FASB further amended the guidance to clarify the implementation on principal versus agent considerations, the identification of performance obligation and the licensing implementation guidance to provide narrow-scope improvements and practical expedients, and technical corrections and improvements. The Company will adopt this standard effective January 1, 2018 and currently anticipates adopting the standard using the modified retrospective method. The Company is still in the process of completing its analysis of the impact this standard will have on the consolidated financial statements including its disclosure. Specifically, while the Company has not yet finalized its analysis of the recognition impact this standard will have on advertising revenue, the Company does not expect the impact to be material; the Company is still assessing the recognition impact of adopting this standard on data licensing and other revenue; and the Company has not completed its assessment of the presentation impact of adoption of the new principal versus agent guidance on its arrangements. As part of the Company’s assessment and implementation plan, the Company is evaluating and implementing changes to its policies, procedures and controls. In March 2017, the FASB issued a new accounting standard update on shortening the premium amortization period for purchased non-contingently callable debt securities. The new guidance shortens the amortization period for the premium on purchased non-contingently callable debt securities to the earliest call date. Currently, entities generally amortize the premium as a yield adjustment over the contractual life of the security. This guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. Early adoption is permitted. The Company is evaluating the impact of adopting this new accounting standard update on the financial statements and related disclosures. With the exception of the standards discussed above, there have been no other recent accounting pronouncements or changes in accounting pronouncements during the six months ended June 30, 2017, as compared to the recent accounting pronouncements described in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016, that are of significance or potential significance to the Company.

Cash, Cash Equivalents and Sh23

Cash, Cash Equivalents and Short-term Investments (Tables)	6 Months Ended
	Jun. 30, 2017
Cash And Cash Equivalents [Abstract]
Cash, Cash and Equivalents and Short-term Investments	Cash, cash equivalents and short-term investments consist of the following (in thousands): June 30, December 31, 2017 2016 Cash and cash equivalents: Cash $ 251,554 $ 253,808 Money market funds 642,605 422,515 U.S. government and agency securities including treasury bills 27,899 12,639 Corporate notes, commercial paper and certificates of deposit 366,265 299,636 Total cash and cash equivalents $ 1,288,323 $ 988,598 Short-term investments: U.S. government and agency securities including treasury bills $ 1,146,379 $ 1,183,768 Corporate notes, commercial paper and certificates of deposit 1,645,210 1,602,213 Total short-term investments $ 2,791,589 $ 2,785,981
Contractual Maturities of Securities Classified as Available-for-Sale	The contractual maturities of securities classified as available-for-sale as of June 30, 2017 were as follows (in thousands): June 30, 2017 Due within one year $ 1,969,093 Due after one year through two years 822,496 Total $ 2,791,589
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): June 30, 2017 Gross Gross Gross Aggregated Amortized Unrealized Unrealized Estimated Costs Gains Losses Fair Value U.S. government and agency securities including treasury bills $ 1,148,568 $ 157 $ (2,346 ) $ 1,146,379 Corporate notes, commercial paper and certificates of deposit 1,645,451 275 (516 ) 1,645,210 Total available-for-sale securities classified as short-term investments $ 2,794,019 $ 432 $ (2,862 ) $ 2,791,589 December 31, 2016 Gross Gross Gross Aggregated Amortized Unrealized Unrealized Estimated Costs Gains Losses Fair Value U.S. government and agency securities including treasury bills $ 1,185,274 $ 136 $ (1,642 ) $ 1,183,768 Corporate notes, commercial paper and certificates of deposit 1,603,048 114 (949 ) 1,602,213 Total available-for-sale securities classified as short-term investments $ 2,788,322 $ 250 $ (2,591 ) $ 2,785,981

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
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 June 30, 2017 and December 31, 2016 based on the three-tier fair value hierarchy (in thousands): June 30, 2017 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 642,605 $ — $ — $ 642,605 Treasury bills 27,899 — — 27,899 Corporate notes — 768 — 768 Commercial paper — 362,485 — 362,485 Certificates of deposit — 3,012 — 3,012 Short-term investments: U.S. government securities — 733,924 — 733,924 Agency securities — 412,455 — 412,455 Corporate notes — 752,793 — 752,793 Commercial paper — 263,409 — 263,409 Certificates of deposit — 629,008 — 629,008 Other current assets: Foreign currency contracts — 2,966 — 2,966 Total $ 670,504 $ 3,160,820 $ — $ 3,831,324 Liabilities Other current liabilities: Foreign currency contracts — 1,472 — 1,472 Total $ — $ 1,472 $ — $ 1,472 December 31, 2016 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 422,515 $ — $ — $ 422,515 Treasury bills 12,639 — — 12,639 Corporate notes — 7,387 — 7,387 Commercial paper — 292,249 — 292,249 Short-term investments: U.S. government securities — 657,502 — 657,502 Agency securities — 526,266 — 526,266 Corporate notes — 689,986 — 689,986 Commercial paper — 311,238 — 311,238 Certificates of deposit — 600,989 — 600,989 Other current assets: Foreign currency contracts — 1,955 — 1,955 Total $ 435,154 $ 3,087,572 $ — $ 3,522,726 Liabilities Other current liabilities: Foreign currency contracts — 500 — 500 Total $ — $ 500 $ — $ 500
Schedule of Fair Values of Outstanding Derivative Instruments	The fair values of outstanding derivative instruments for the periods presented on a gross basis are as follows (in thousands): June 30, December 31, Balance Sheet Location 2017 2016 Assets Foreign currency contracts not designated as hedging instruments Other current assets $ 2,966 $ 1,955 Liabilities Foreign currency contracts not designated as hedging instruments Other current liabilities $ 1,472 $ 500

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	6 Months Ended
	Jun. 30, 2017
Property Plant And Equipment [Abstract]
Schedule of Property and Equipment, Net	The following table presents the detail of property and equipment, net for the periods presented (in thousands): June 30, December 31, 2017 2016 Property and equipment, net Equipment $ 990,795 $ 909,797 Furniture and leasehold improvements 319,414 304,613 Capitalized software 398,983 353,163 Construction in progress 71,694 74,255 Total 1,780,886 1,641,828 Less: Accumulated depreciation and amortization (999,614 ) (857,927 ) Property and equipment, net $ 781,272 $ 783,901

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill Activities	The following table presents the goodwill activities for the periods presented (in thousands): Goodwill Balance as of December 31, 2016 $ 1,185,315 Foreign currency translation adjustment and other 874 Balance as of June 30, 2017 $ 1,186,189
Schedule of Intangible Assets	The following table presents the detail of intangible assets for the periods presented (in thousands): Gross Carrying Accumulated Net Carrying Value Amortization Value June 30, 2017: Patents and developed technologies $ 123,324 $ (63,434 ) $ 59,890 Publisher and advertiser relationships 53,100 (47,699 ) 5,401 Total $ 176,424 $ (111,133 ) $ 65,291 December 31, 2016: Patents and developed technologies $ 122,611 $ (47,160 ) $ 75,451 Publisher and advertiser relationships 53,100 (33,217 ) 19,883 Total $ 175,711 $ (80,377 ) $ 95,334
Schedule of Estimated Future Amortization Expenses	Estimated future amortization expense as of June 30, 2017 is as follows (in thousands): Remainder of 2017 $ 15,830 2018 16,023 2019 8,496 2020 6,222 2021 5,826 Thereafter 12,894 Total $ 65,291

Accrued and Other Current Lia27

Accrued and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2017
Payables And Accruals [Abstract]
Accrued and Other Current Liabilities	The following table presents the detail of accrued and other current liabilities for the periods presented (in thousands): June 30, December 31, 2017 2016 Accrued compensation $ 73,833 $ 82,354 Accrued restructuring 43,937 55,942 Accrued publisher, content and ad network costs 21,816 44,362 Deferred revenue 22,700 33,659 Accrued tax liabilities 30,945 29,558 Accrued fixed assets and maintenance 25,214 25,265 Accrued other 88,602 109,797 Total $ 307,047 $ 380,937

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Components of Notes	The Notes consisted of the following (in thousands): June 30, 2017 December 31, 2016 2019 Notes 2021 Notes 2019 Notes 2021 Notes Principal amounts: Principal $ 935,000 $ 954,000 $ 935,000 $ 954,000 Unamortized initial purchasers' discount and debt discount (1) (112,758 ) (193,774 ) (136,376 ) (213,657 ) Net carrying amount $ 822,242 $ 760,226 $ 798,624 $ 740,343 Carrying amount of the equity component (2) $ 222,826 $ 283,283 $ 222,826 $ 283,283 (1) (2)

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
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 June 30, Six Months Ended June 30, 2017 2016 2017 2016 Net loss $ (116,488 ) $ (107,217 ) $ (178,047 ) $ (186,948 ) Basic shares: Weighted-average common shares outstanding 734,178 704,174 730,348 700,920 Weighted-average restricted stock subject to repurchase (4,109 ) (5,848 ) (4,265 ) (5,961 ) Weighted-average shares used to compute basic net loss per share 730,069 698,326 726,083 694,959 Diluted shares: Weighted-average shares used to compute diluted net loss per share 730,069 698,326 726,083 694,959 Net loss per share attributable to common stockholders: Basic $ (0.16 ) $ (0.15 ) $ (0.25 ) $ (0.27 ) Diluted $ (0.16 ) $ (0.15 ) $ (0.25 ) $ (0.27 )
Summary of Potential Common Shares Excluded from Calculation of Diluted Net Loss Per Share Attributable to Common Stockholders	The following number of potential common shares at the end of each period 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 and Six Months Ended June 30, 2017 2016 RSUs 37,979 58,806 Warrants 24,329 24,329 Stock options 5,301 9,340 Shares subject to repurchase and others 6,410 10,457

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2017
Stockholders Equity Note [Abstract]
Summary of Restricted Stock Activity	The activities for the restricted common stock issued to employees for the six months ended June 30, 2017 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, 2016 5,097 $ 23.04 Vested (1,166 ) $ 23.76 Canceled (441 ) $ 38.03 Unvested restricted common stock at June 30, 2017 3,490 $ 20.90
Summary of Stock Option Activity	A summary of stock option activity for the six months ended June 30, 2017 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, 2016 8,723 $ 7.71 $ 4.25 $ 98,240 Options exercised (3,239 ) $ 2.26 Options canceled (183 ) $ 2.72 Outstanding at June 30, 2017 5,301 $ 11.20 5.17 $ 56,414 Exercisable at June 30, 2017 4,192 $ 8.73 4.42 $ 49,988
Summary of RSU Activity Excluding PRSU	The following table summarizes the activity related to the Company’s RSUs, excluding PRSUs, for the six months ended June 30, 2017. 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, 2016 48,069 $ 22.64 Granted 9,111 $ 15.23 Vested (11,138 ) $ 22.29 Canceled (8,063 ) $ 22.61 Unvested and outstanding at June 30, 2017 37,979 $ 20.97
Compensation Expense Allocated	Stock-based compensation expense is allocated based on the cost center to which the award holder belongs. Total stock-based compensation expense by function is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Cost of revenue $ 6,253 $ 7,858 $ 12,205 $ 15,826 Research and development 63,625 90,916 128,011 166,495 Sales and marketing 20,694 45,856 45,783 91,957 General and administrative 22,824 23,065 44,394 44,333 Total stock-based compensation expense $ 113,396 $ 167,695 $ 230,393 $ 318,611

Operations by Geographic Area (

Operations by Geographic Area (Tables)	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Revenue by Geography	Revenue by geography is based on the billing addresses of the customers. The following table sets forth revenue by services and revenue by geographic area (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Revenue by services: Advertising services $ 489,148 $ 534,524 $ 962,928 $ 1,065,265 Data licensing and other 84,707 67,434 159,178 131,214 Total revenue $ 573,855 $ 601,958 $ 1,122,106 $ 1,196,479 Three Months Ended June 30, Six Months Ended June 30, 2017 2016 2017 2016 Revenue by geographic area: United States $ 334,675 $ 360,676 $ 675,259 $ 750,943 International 239,180 241,282 446,847 445,536 Total revenue $ 573,855 $ 601,958 $ 1,122,106 $ 1,196,479
Property and Equipment Net by Geographic Area	The following table sets forth property and equipment, net by geographic area (in thousands): June 30, December 31, 2017 2016 Property and equipment, net: United States $ 730,269 $ 728,429 International 51,003 55,472 Total property and equipment, net $ 781,272 $ 783,901

Restructuring Charges (Tables)

Restructuring Charges (Tables)	6 Months Ended
	Jun. 30, 2017
Restructuring And Related Activities [Abstract]
Summary of Activities Related to Restructuring Charges	The following table summarizes the activities related to restructuring charges, as discussed above (in thousands): 2016 Employee 2016 Termination Plan Lease Plan Charges $ 21,611 $ 79,685 Cash payment (11,629 ) (3,562 ) Non-cash and other adjustments (6,357 ) (19,577 ) Accrued as of December 31, 2016 $ 3,625 $ 56,546 Charges (1) $ 788 $ 1,539 Cash payment (4,240 ) (11,319 ) Non-cash and other adjustments 108 14 Accrued as of June 30, 2017 $ 281 $ 46,780 Reflected in consolidated balance sheets as of June 30, 2017: Accrued and other current liabilities $ 281 $ 43,656 Other long-term liabilities $ — $ 3,124 (1) recorded a reduction to restructuring charges of $0.2 million within sales and marketing in the consolidated statements of operations. recorded restructuring charges of $1.3 million within sales and marketing, $0.6 million within research and development, $0.3 million within general and administrative and $0.1 million within cost of revenue in the consolidated statements of operations.

Description of Business and S33

Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jan. 01, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Increase in deferred tax assets with corresponding increase in valuation allowance	$ 930
Increase in accumulated deficit resulting from the adoption of new guidance		$ 13.3

Cash, Cash Equivalents and Sh34

Cash, Cash Equivalents and Short-term Investments - Cash, Cash and Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Cash and cash equivalents:
Cash	$ 251,554	$ 253,808
Cash and cash equivalents	1,288,323	988,598	$ 947,710	$ 911,471
Short-term investments:
Short-term investments	2,791,589	2,785,981
Money Market Funds
Cash and cash equivalents:
Cash and cash equivalents	642,605	422,515
U.S. Government and Agency Securities Including Treasury Bills
Cash and cash equivalents:
Cash and cash equivalents	27,899	12,639
Short-term investments:
Short-term investments	1,146,379	1,183,768
Corporate Notes, Commercial Paper and Certificates of Deposit
Cash and cash equivalents:
Cash and cash equivalents	366,265	299,636
Short-term investments:
Short-term investments	$ 1,645,210	$ 1,602,213

Cash, Cash Equivalents and Sh35

Cash, Cash Equivalents and Short-term Investments - Contractual Maturities of Securities Classified as Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Cash And Cash Equivalents And Marketable Securities [Abstract]
Due within one year	$ 1,969,093
Due after one year through two years	822,496
Total	$ 2,791,589	$ 2,785,981

Cash, Cash Equivalents and Sh36

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 ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities [Line Items]
Gross Amortized Costs	$ 2,794,019	$ 2,788,322
Gross Unrealized Gains	432	250
Gross Unrealized Losses	(2,862)	(2,591)
Aggregated Estimated Fair Value	2,791,589	2,785,981
U.S. Government and Agency Securities Including Treasury Bills
Schedule Of Available For Sale Securities [Line Items]
Gross Amortized Costs	1,148,568	1,185,274
Gross Unrealized Gains	157	136
Gross Unrealized Losses	(2,346)	(1,642)
Aggregated Estimated Fair Value	1,146,379	1,183,768
Corporate Notes, Commercial Paper and Certificates of Deposit
Schedule Of Available For Sale Securities [Line Items]
Gross Amortized Costs	1,645,451	1,603,048
Gross Unrealized Gains	275	114
Gross Unrealized Losses	(516)	(949)
Aggregated Estimated Fair Value	$ 1,645,210	$ 1,602,213

Cash, Cash Equivalents and Sh37

Cash, Cash Equivalents and Short-term Investments - Additional Information (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Investments Debt And Equity Securities [Abstract]
Securities continuous loss position for 12 months or longer	$ 0
Impairment loss on securities	$ 0	$ 0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Net Asset (Liability) [Abstract]
Short-term investments	$ 2,791,589	$ 2,785,981
Other current assets	2,966	1,955
Other current liabilities	1,472	500
Fair Value, Measurements, Recurring
Fair Value, Net Asset (Liability) [Abstract]
Total	3,831,324	3,522,726
Total	1,472	500
Fair Value, Measurements, Recurring | Agency Securities
Fair Value, Net Asset (Liability) [Abstract]
Short-term investments	412,455	526,266
Fair Value, Measurements, Recurring | Money Market Funds
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	642,605	422,515
Fair Value, Measurements, Recurring | Treasury Bills
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	27,899	12,639
Fair Value, Measurements, Recurring | Corporate Notes
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	768	7,387
Short-term investments	752,793	689,986
Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	362,485	292,249
Short-term investments	263,409	311,238
Fair Value, Measurements, Recurring | Certificates of Deposit
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	3,012
Short-term investments	629,008	600,989
Fair Value, Measurements, Recurring | US Government Securities
Fair Value, Net Asset (Liability) [Abstract]
Short-term investments	733,924	657,502
Fair Value, Measurements, Recurring | Foreign currency contracts
Fair Value, Net Asset (Liability) [Abstract]
Other current assets	2,966	1,955
Other current liabilities	1,472	500
Level 1 | Fair Value, Measurements, Recurring
Fair Value, Net Asset (Liability) [Abstract]
Total	670,504	435,154
Level 1 | Fair Value, Measurements, Recurring | Money Market Funds
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	642,605	422,515
Level 1 | Fair Value, Measurements, Recurring | Treasury Bills
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	27,899	12,639
Level 2 | Fair Value, Measurements, Recurring
Fair Value, Net Asset (Liability) [Abstract]
Total	3,160,820	3,087,572
Total	1,472	500
Level 2 | Fair Value, Measurements, Recurring | Agency Securities
Fair Value, Net Asset (Liability) [Abstract]
Short-term investments	412,455	526,266
Level 2 | Fair Value, Measurements, Recurring | Corporate Notes
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	768	7,387
Short-term investments	752,793	689,986
Level 2 | Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	362,485	292,249
Short-term investments	263,409	311,238
Level 2 | Fair Value, Measurements, Recurring | Certificates of Deposit
Fair Value, Net Asset (Liability) [Abstract]
Cash equivalents	3,012
Short-term investments	629,008	600,989
Level 2 | Fair Value, Measurements, Recurring | US Government Securities
Fair Value, Net Asset (Liability) [Abstract]
Short-term investments	733,924	657,502
Level 2 | Fair Value, Measurements, Recurring | Foreign currency contracts
Fair Value, Net Asset (Liability) [Abstract]
Other current assets	2,966	1,955
Other current liabilities	$ 1,472	$ 500

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Notional principal of foreign currency contracts outstanding	$ 553,600		$ 553,600		$ 536,900
Net gain (losses) on foreign currency contracts	5,600	$ (6,500)	2,400	$ (4,700)
Convertible Notes | Senior Notes Due 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument, principal amount	$ 935,000		$ 935,000		935,000	$ 935,000
Debt Instrument, percentage	0.25%		0.25%			0.25%
Debt Instrument, due date			2,019
Convertible Notes | Senior Notes Due 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument, principal amount	$ 954,000		$ 954,000		$ 954,000	$ 954,000
Debt Instrument, percentage	1.00%		1.00%			1.00%
Debt Instrument, due date			2,021
Convertible Notes | Level 2 | Senior Notes Due 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of notes based on a market approach	$ 882,600		$ 882,600
Convertible Notes | Level 2 | Senior Notes Due 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of notes based on a market approach	$ 872,100		$ 872,100

Fair Value Measurements - Sch40

Fair Value Measurements - Schedule of Fair Values of Outstanding Derivative Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Foreign currency contracts not designated as hedging instruments	$ 2,966	$ 1,955
Liabilities
Foreign currency contracts not designated as hedging instruments	$ 1,472	$ 500

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property and equipment, net
Property and equipment, gross	$ 1,780,886	$ 1,641,828
Less: Accumulated depreciation and amortization	(999,614)	(857,927)
Property and equipment, net	781,272	783,901
Equipment
Property and equipment, net
Property and equipment, gross	990,795	909,797
Furniture and Leasehold Improvements
Property and equipment, net
Property and equipment, gross	319,414	304,613
Capitalized Software
Property and equipment, net
Property and equipment, gross	398,983	353,163
Construction in Progress
Property and equipment, net
Property and equipment, gross	$ 71,694	$ 74,255

Goodwill and Intangible Asset42

Goodwill and Intangible Assets - Schedule of Goodwill Activities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017USD ($)
Goodwill
Beginning balance	$ 1,185,315
Foreign currency translation adjustment and other	874
Ending balance	$ 1,186,189

Goodwill and Intangible Asset43

Goodwill and Intangible Assets - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Impairment charges on goodwill			$ 0		$ 0
Amortization of intangible assets	$ 14,300,000	$ 12,800,000	$ 30,500,000	$ 25,500,000

Goodwill and Intangible Asset44

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 176,424	$ 175,711
Accumulated Amortization	(111,133)	(80,377)
Net Carrying Value	65,291	95,334
Patents and Developed Technologies
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	123,324	122,611
Accumulated Amortization	(63,434)	(47,160)
Net Carrying Value	59,890	75,451
Publisher and Advertiser Relationships
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	53,100	53,100
Accumulated Amortization	(47,699)	(33,217)
Net Carrying Value	$ 5,401	$ 19,883

Goodwill and Intangible Asset45

Goodwill and Intangible Assets - Schedule of Estimated Future Amortization Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Remainder of 2017	$ 15,830
2,018	16,023
2,019	8,496
2,020	6,222
2,021	5,826
Thereafter	12,894
Net Carrying Value	$ 65,291	$ 95,334

Accrued and Other Current Lia46

Accrued and Other Current Liabilities - Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables And Accruals [Abstract]
Accrued compensation	$ 73,833	$ 82,354
Accrued restructuring	43,937	55,942
Accrued publisher, content and ad network costs	21,816	44,362
Deferred revenue	22,700	33,659
Accrued tax liabilities	30,945	29,558
Accrued fixed assets and maintenance	25,214	25,265
Accrued other	88,602	109,797
Total	$ 307,047	$ 380,937

Investments in Privately-Held47

Investments in Privately-Held Companies - Additional Information (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Schedule Of Investments [Abstract]
Cost method investments	$ 35,200,000			$ 35,200,000		$ 90,200,000
Other than temporary impairment charge	$ 55,000,000	$ 0	$ 0	$ 55,000,000	$ 0

Convertible Senior Notes - Addi

Convertible Senior Notes - Additional Information (Details) - Convertible Notes - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2014	Dec. 31, 2016
Debt Instrument [Line Items]
Initial purchasers' discount						$ 28,300
Debt issuance costs						500
Proceeds from offerings, net of transaction costs						1,860,000
Debt Instrument, frequency of periodic payment				semi-annually
Debt Instrument, date of first required payment				Mar. 15, 2015
Debt Instrument Payment Terms				The interest rates are fixed at 0.25% and 1.00% per annum for the 2019 Notes and the 2021 Notes, respectively, and are payable semi-annually in arrears on March 15 and September 15 of each year, commencing on March 15, 2015.
Amortization of initial purchasers' discount and debt discount, prior to capitalization of interest		$ 22,100	$ 20,900	$ 43,500	$ 41,300
Coupon interest expense		3,000	$ 3,000	5,900	$ 6,000
Senior Notes Due 2019
Debt Instrument [Line Items]
Debt instrument, principal amount		935,000		935,000		$ 935,000	$ 935,000
Initial purchasers' discount	[1]	$ 112,758		$ 112,758			136,376
Debt instrument, interest rate percentage		0.25%		0.25%		0.25%
Remaining period for convertible debt				26 months
Senior Notes Due 2021
Debt Instrument [Line Items]
Debt instrument, principal amount		$ 954,000		$ 954,000		$ 954,000	954,000
Initial purchasers' discount	[1]	$ 193,774		$ 193,774			$ 213,657
Debt instrument, interest rate percentage		1.00%		1.00%		1.00%
Remaining period for convertible debt				50 months
[1]	Included in the consolidated balance sheets within convertible notes and amortized over the remaining lives of the Notes.

Convertible Senior Notes - Comp

Convertible Senior Notes - Components of Notes (Details) - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2014
Principal amounts:
Net carrying amount		$ 1,582,468	$ 1,538,967
Convertible Notes
Principal amounts:
Unamortized initial purchasers' discount and debt discount				$ (28,300)
Convertible Notes | Senior Notes Due 2019
Principal amounts:
Debt instrument, principal amount		935,000	935,000	935,000
Unamortized initial purchasers' discount and debt discount	[1]	(112,758)	(136,376)
Net carrying amount		822,242	798,624
Carrying amount of the equity component	[2]	222,826	222,826
Convertible Notes | Senior Notes Due 2021
Principal amounts:
Debt instrument, principal amount		954,000	954,000	$ 954,000
Unamortized initial purchasers' discount and debt discount	[1]	(193,774)	(213,657)
Net carrying amount		760,226	740,343
Carrying amount of the equity component	[2]	$ 283,283	$ 283,283
[1]	Included in the consolidated balance sheets within convertible notes and amortized over the remaining lives of the Notes.
[2]	Included in the consolidated balance sheets within additional paid-in capital.

Net Loss Per Share - Basic and

Net Loss Per Share - Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net loss	$ (116,488)	$ (107,217)	$ (178,047)	$ (186,948)
Basic shares:
Weighted-average common shares outstanding	734,178	704,174	730,348	700,920
Weighted-average restricted stock subject to repurchase	(4,109)	(5,848)	(4,265)	(5,961)
Weighted-average shares used to compute basic net loss per share	730,069	698,326	726,083	694,959
Diluted shares:
Weighted-average shares used to compute diluted net loss per share	730,069	698,326	726,083	694,959
Net loss per share attributable to common stockholders:
Basic	$ (0.16)	$ (0.15)	$ (0.25)	$ (0.27)
Diluted	$ (0.16)	$ (0.15)	$ (0.25)	$ (0.27)

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) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
RSUs
Earnings Per Share Basic [Line Items]
Anti-dilutive securities excluded from the computation of diluted net income per share	37,979	58,806	37,979	58,806
Warrants
Earnings Per Share Basic [Line Items]
Anti-dilutive securities excluded from the computation of diluted net income per share	24,329	24,329	24,329	24,329
Stock Options
Earnings Per Share Basic [Line Items]
Anti-dilutive securities excluded from the computation of diluted net income per share	5,301	9,340	5,301	9,340
Restricted Common Stock and Others
Earnings Per Share Basic [Line Items]
Anti-dilutive securities excluded from the computation of diluted net income per share	6,410	10,457	6,410	10,457

Net Loss Per Share - Additional

Net Loss Per Share - Additional Information (Details)	6 Months Ended
	Jun. 30, 2017$ / sharesshares
Earnings Per Share [Abstract]
Conversion Price	$ 77.64
Conversion spread will have a dilutive impact on diluted net income per share of common stock | shares	24,300,000
Exercise price of the warrants	$ 105.28

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock upon purchases under employee stock purchase plan, shares			1,100,000	1,300,000
Employee stock purchase plan (ESOP), weighted average purchase price of shares purchased			$ 12.43	$ 11.99
Gross unamortized stock-based compensation expense related to unvested awards	$ 738.2		$ 738.2
Unrecognized share-based compensation expense, weighted average recognition period			2 years 3 months 18 days
Internal Use Software and Website Development Costs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, capitalized amount	14.2	$ 17.9	$ 30.3	$ 40.5
Restricted Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, vested			1,166,000
Employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options exercised, intrinsic value	6.7	12.4	$ 44.1	32.2
PRSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period			1 year
Number of Shares, granted			318,400		165,833
Shares granted at target level			100.00%		100.00%
Weighted Average Grant Date Fair Value Per Share, Granted			$ 15.28
Number of Shares, vested			117,808
PRSUs and TSR RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional number of shares, that will vest based on performance goals and total shareholder return targets			1,408,533
TSR RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period			2 years
Number of Shares, granted			134,400
Weighted Average Grant Date Fair Value Per Share, Granted			$ 13.02
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, granted			9,111,000
Weighted Average Grant Date Fair Value Per Share, Granted			$ 15.23
Number of Shares, vested			11,138,000
Fair value of restricted stock units vested	$ 86.1	119.8	$ 187	212.4
Maximum | Restricted Common Stock | All Acquisitions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity compensation service period			4 years
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issuance	11,300,000		11,300,000
Outstanding shares of common stock percentage			1.00%
Share-based compensation expense	$ 1.8	$ 5.7	$ 4.4	$ 11.4
2013 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares initially reserved	68,300,000		68,300,000
Number of shares available for issuance	60,000,000		60,000,000
Outstanding shares of common stock percentage			5.00%
2007 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued during the period			0

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Restricted Stock Activity (Details) - Restricted Common Stock shares in Thousands	6 Months Ended
	Jun. 30, 2017$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Unvested Shares, beginning of period | shares	5,097
Number of Shares, vested | shares	(1,166)
Number of Shares, Canceled | shares	(441)
Number of Unvested Shares, end of period | shares	3,490
Weighted Average Grant Date Fair Value Per Share, beginning of period | $ / shares	$ 23.04
Weighted Average Grant Date Fair Value Per Share, Vested | $ / shares	23.76
Weighted Average Grant Date Fair Value Per Share, Canceled | $ / shares	38.03
Weighted Average Grant Date Fair Value Per Share, end of period | $ / shares	$ 20.90

Stockholders' Equity - Summar55

Stockholders' Equity - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Options Outstanding - Number of Shares
Outstanding at beginning of period	8,723
Options exercised	(3,239)
Options canceled	(183)
Outstanding at end of period	5,301	8,723
Exercisable at end of period	4,192
Options Outstanding - Weighted-Average Exercise Price Per Share
Outstanding at beginning of period	$ 7.71
Options exercised	2.26
Options canceled	2.72
Outstanding at end of period	11.20	$ 7.71
Exercisable at end of period	$ 8.73
Options Outstanding - Weighted-Average Remaining Contractual Life
Outstanding	5 years 2 months 1 day	4 years 3 months
Exercisable at end of period	4 years 5 months 1 day
Options Outstanding - Aggregate Intrinsic Value
Outstanding	$ 56,414	$ 98,240
Exercisable at end of period	$ 49,988

Stockholders' Equity - Summar56

Stockholders' Equity - Summary of RSU Activity Excluding PRSU (Details) - RSUs shares in Thousands	6 Months Ended
	Jun. 30, 2017$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Unvested Shares, beginning of period | shares	48,069
Number of Shares, granted | shares	9,111
Number of Shares, vested | shares	(11,138)
Number of Shares, Canceled | shares	(8,063)
Number of Unvested Shares, end of period | shares	37,979
Weighted Average Grant Date Fair Value Per Share, beginning of period | $ / shares	$ 22.64
Weighted Average Grant Date Fair Value Per Share, Granted | $ / shares	15.23
Weighted Average Grant Date Fair Value Per Share, Vested | $ / shares	22.29
Weighted Average Grant Date Fair Value Per Share, Canceled | $ / shares	22.61
Weighted Average Grant Date Fair Value Per Share, end of period | $ / shares	$ 20.97

Stockholders' Equity - Compensa

Stockholders' Equity - Compensation Expense Allocated (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 113,396	$ 167,695	$ 230,393	$ 318,611
Cost of Revenue
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	6,253	7,858	12,205	15,826
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	63,625	90,916	128,011	166,495
Sales and Marketing
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	20,694	45,856	45,783	91,957
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 22,824	$ 23,065	$ 44,394	$ 44,333

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 3,413	$ 2,641	$ 6,607	$ 4,669
Unrecognized tax benefits, period change	12,800		23,500
Unrecognized tax benefits	293,000		293,000
Unrecognized tax benefits, if recognized would not affect the annual effective tax rate	286,000		286,000
Unrecognized tax benefits, if recognized would affect the annual effective tax rate	$ 7,000		$ 7,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	6 Months Ended
	Jun. 30, 2017USD ($)
Other Commitments [Line Items]
Expiration year of operating lease	2,028
Revolving Credit Facility
Other Commitments [Line Items]
Unsecured revolving credit facility	$ 1,000,000,000
Line of credit facility, expiration date	Oct. 22, 2018
Line of credit facility amount	$ 0

Operations by Geographic Area -

Operations by Geographic Area - Revenue by Services and Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue:
Revenue	$ 573,855	$ 601,958	$ 1,122,106	$ 1,196,479
United States
Revenue:
Revenue	334,675	360,676	675,259	750,943
International
Revenue:
Revenue	239,180	241,282	446,847	445,536
Advertising Services
Revenue:
Revenue	489,148	534,524	962,928	1,065,265
Data Licensing And Other
Revenue:
Revenue	$ 84,707	$ 67,434	$ 159,178	$ 131,214

Operations by Geographic Area61

Operations by Geographic Area - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)Country
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	$ 573,855	$ 601,958	$ 1,122,106	$ 1,196,479
International
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	239,180	241,282	446,847	$ 445,536
Revenue | Japan
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	$ 74,200	$ 61,200	$ 146,800
Revenue | International
Revenues From External Customers And Long Lived Assets [Line Items]
Number of individual country that contributed in excess of ten percent to revenue | Country				0
Revenue | Geographic Concentration Risk | Japan
Revenues From External Customers And Long Lived Assets [Line Items]
Concentration risk percentage	13.00%	10.00%	13.00%

Operations by Geographic Area62

Operations by Geographic Area - Property and Equipment Net by Geographic Area (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property and equipment, net:
Property and equipment, net	$ 781,272	$ 783,901
United States
Property and equipment, net:
Property and equipment, net	730,269	728,429
International
Property and equipment, net:
Property and equipment, net	$ 51,003	$ 55,472

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details)	6 Months Ended
	Jun. 30, 2017USD ($)
Square Inc
Related Party Transaction [Line Items]
Agreement consideration amount	$ 0

Restructuring Charges - Additio

Restructuring Charges - Additional Information (Details)	Oct. 25, 2016	Jun. 30, 2017
Restructuring Cost And Reserve [Line Items]
Percentage on employees reduction plan	9.00%
Restructuring and related activities, lease terms expiration year		2,028
2016 Lease Plan | Abandonment Excess Office Space
Restructuring Cost And Reserve [Line Items]
Restructuring and related activities, initiation date		Dec. 17, 2016
Restructuring and related activities, lease terms expiration year		2,028

Restructuring Charges - Summary

Restructuring Charges - Summary of Activities Related to Restructuring Charges (Details) - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2017		Dec. 31, 2016
Restructuring Cost And Reserve [Line Items]
Accrued restructuring, reflected in accrued and other current liabilities	$ 43,937		$ 55,942
2016 Employee Termination Plan
Restructuring Cost And Reserve [Line Items]
Charges	788	[1]	21,611
Cash payment	(4,240)		(11,629)
Non-cash and other adjustments	108		(6,357)
Accrued restructuring	281		3,625
Accrued restructuring, reflected in accrued and other current liabilities	281
2016 Lease Plan
Restructuring Cost And Reserve [Line Items]
Charges	1,539	[1]	79,685
Cash payment	(11,319)		(3,562)
Non-cash and other adjustments	14		(19,577)
Accrued restructuring	46,780		$ 56,546
Accrued restructuring, reflected in accrued and other current liabilities	43,656
Accrued restructuring, reflected in other long-term liabilities	$ 3,124
[1]	For the three months ended June 30, 2017, the Company recorded a reduction to restructuring charges of $0.2 million within sales and marketing in the consolidated statements of operations. For the six months ended June 30, 2017, the Company recorded restructuring charges of $1.3 million within sales and marketing, $0.6 million within research and development, $0.3 million within general and administrative and $0.1 million within cost of revenue in the consolidated statements of operations.

Restructuring Charges - Summa66

Restructuring Charges - Summary of Activities Related to Restructuring Charges (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017
Sales and Marketing
Restructuring Cost And Reserve [Line Items]
Reduction to restructuring charges	$ 0.2
Charges		$ 1.3
Research and Development
Restructuring Cost And Reserve [Line Items]
Charges		0.6
General and Administrative
Restructuring Cost And Reserve [Line Items]
Charges		0.3
Cost of Revenue
Restructuring Cost And Reserve [Line Items]
Charges		$ 0.1