Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2020	Oct. 23, 2020
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
Document Transition Report	false
Entity File Number	001-38872
Entity Registrant Name	Pinterest, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-3607129
Entity Address, Address Line One	505 Brannan Street
Entity Address, City or Town	San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94107
City Area Code	415
Local Phone Number	762-7100
Title of 12(b) Security	Class A Common Stock, $0.00001 par value
Trading Symbol	PINS
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Document Fiscal Period Focus	Q3
Amendment Flag	false
Document Fiscal Year Focus	2020
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0001506293
Class A Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		510,856,241
Class B Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		107,214,170

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 652,723	$ 649,666
Marketable securities	996,392	1,063,679
Accounts receivable, net of allowances of $5,670 and $2,851 as of September 30, 2020 and December 31, 2019, respectively	339,274	316,367
Prepaid expenses and other current assets	44,537	37,522
Total current assets	2,032,926	2,067,234
Property and equipment, net	76,294	91,992
Operating lease right-of-use assets	164,803	188,251
Goodwill and intangible assets, net	13,814	14,576
Restricted cash	9,221	25,339
Other assets	3,980	5,925
Total assets	2,301,038	2,393,317
Current liabilities:
Accounts payable	41,703	34,334
Accrued expenses and other current liabilities	147,946	141,823
Total current liabilities	189,649	176,157
Operating lease liabilities	150,162	173,392
Other liabilities	26,623	20,063
Total liabilities	366,434	369,612
Commitments and contingencies
Stockholders’ equity:
Common stock	6	6
Additional paid-in capital	4,475,425	4,229,778
Accumulated other comprehensive income	2,063	647
Accumulated deficit	(2,542,890)	(2,206,726)
Total stockholders’ equity	1,934,604	2,023,705
Total liabilities and stockholders’ equity	$ 2,301,038	$ 2,393,317

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Allowances	$ 5,670	$ 2,851
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	6,666,667,000	6,666,667,000
Common stock, shares issued (in shares)	507,248,000	360,850,000
Common stock, shares outstanding (in shares)	507,248,000	360,850,000
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, shares authorized (in shares)	1,333,333,000	1,333,333,000
Common stock, shares issued (in shares)	107,995,000	209,054,000
Common stock, shares outstanding (in shares)	107,995,000	209,054,000

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Revenue	$ 442,616	$ 279,703	$ 987,041	$ 742,863
Costs and expenses:
Cost of revenue	112,844	83,520	320,335	262,629
Research and development	160,187	167,703	442,484	1,042,026
Sales and marketing	118,531	110,740	322,041	484,053
General and administrative	148,087	51,450	249,834	299,834
Total costs and expenses	539,649	413,413	1,334,694	2,088,542
Loss from operations	(97,033)	(133,710)	(347,653)	(1,345,679)
Interest income	2,896	9,837	14,265	22,023
Interest expense and other income (expense), net	(51)	(1,056)	(2,144)	(2,004)
Loss before provision for income taxes	(94,188)	(124,929)	(335,532)	(1,325,660)
Provision for (benefit from) income taxes	32	(197)	632	(7)
Net loss	$ (94,220)	$ (124,732)	$ (336,164)	$ (1,325,653)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.16)	$ (0.23)	$ (0.57)	$ (4.15)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted (in shares)	603,490	546,126	588,895	319,490

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (94,220)	$ (124,732)	$ (336,164)	$ (1,325,653)
Other comprehensive income (loss), net of taxes:
Change in unrealized gain (loss) on available-for-sale marketable securities	(1,772)	0	1,634	1,934
Change in foreign currency translation adjustment	98	(147)	(218)	(137)
Comprehensive loss	$ (95,894)	$ (124,879)	$ (334,748)	$ (1,323,856)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Balance (in shares) at Dec. 31, 2018	308,373
Balance at Dec. 31, 2018	$ 1,465,399
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of redeemable convertible preferred stock and redeemable convertible preferred stock warrants to common stock in connection with initial public offering (in shares)	(308,373)
Conversion of redeemable convertible preferred stock and redeemable convertible preferred stock warrants to common stock in connection with initial public offering	$ (1,465,399)
Balance (in shares) at Sep. 30, 2019	0
Balance at Sep. 30, 2019	$ 0
Beginning balance (in shares) at Dec. 31, 2018		127,298
Beginning balance at Dec. 31, 2018	(594,563)	$ 1	$ 252,212	$ (1,421)	$ (845,355)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Release of restricted stock units (in shares)		25,108
Release of restricted stock units	0
Shares repurchased for tax withholdings on release of restricted stock units	(424,965)		(424,965)
Conversion of redeemable convertible preferred stock and redeemable convertible preferred stock warrants to common stock in connection with initial public offering (in shares)		308,622
Conversion of redeemable convertible preferred stock and redeemable convertible preferred stock warrants to common stock in connection with initial public offering	1,470,077	$ 3	1,470,074
Issuance of common stock in connection with initial public offering net of underwriters' discounts and commissions and offering costs (in shares)		86,250
Issuance of common stock in connection with initial public offering net of underwriters' discounts and commissions and offering costs	1,563,383	$ 1	1,563,382
Issuance of common stock for cash upon exercise of stock options, net (in shares)		287
Issuance of common stock for cash upon exercise of stock options, net	744		744
Share-based compensation	1,265,581		1,265,581
Other comprehensive income (loss)	1,797			1,797
Net loss	(1,325,653)				(1,325,653)
Ending balance (in shares) at Sep. 30, 2019		547,565
Ending balance at Sep. 30, 2019	$ 1,956,401	$ 5	4,127,028	376	(2,171,008)
Balance (in shares) at Jun. 30, 2019	0
Balance at Jun. 30, 2019	$ 0
Balance (in shares) at Sep. 30, 2019	0
Balance at Sep. 30, 2019	$ 0
Beginning balance (in shares) at Jun. 30, 2019		542,704
Beginning balance at Jun. 30, 2019	2,073,240	$ 5	4,118,988	523	(2,046,276)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Release of restricted stock units (in shares)		4,851
Release of restricted stock units	0
Shares repurchased for tax withholdings on release of restricted stock units	(122,290)		(122,290)
Issuance of common stock for cash upon exercise of stock options, net (in shares)		10
Issuance of common stock for cash upon exercise of stock options, net	42		42
Share-based compensation	130,288		130,288
Other comprehensive income (loss)	(147)			(147)
Net loss	(124,732)				(124,732)
Ending balance (in shares) at Sep. 30, 2019		547,565
Ending balance at Sep. 30, 2019	$ 1,956,401	$ 5	4,127,028	376	(2,171,008)
Balance (in shares) at Dec. 31, 2019	0
Balance at Dec. 31, 2019	$ 0
Balance (in shares) at Sep. 30, 2020	0
Balance at Sep. 30, 2020	$ 0
Beginning balance (in shares) at Dec. 31, 2019		569,904
Beginning balance at Dec. 31, 2019	2,023,705	$ 6	4,229,778	647	(2,206,726)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Release of restricted stock units (in shares)		13,785
Release of restricted stock units	0
Shares repurchased for tax withholdings on release of restricted stock units	$ (56,894)		(56,894)
Issuance of common stock for cash upon exercise of stock options, net (in shares)	28,855	28,855
Issuance of common stock for cash upon exercise of stock options, net	$ 64,992		64,992
Issuance of common stock related to charitable contributions (in shares)		150
Issuance of common stock related to charitable contributions	2,748		2,748
Issuance of restricted stock awards (in shares)		2,549
Issuance of restricted stock awards	0
Share-based compensation	234,801		234,801
Other comprehensive income (loss)	1,416			1,416
Net loss	(336,164)				(336,164)
Ending balance (in shares) at Sep. 30, 2020		615,243
Ending balance at Sep. 30, 2020	$ 1,934,604	$ 6	4,475,425	2,063	(2,542,890)
Balance (in shares) at Jun. 30, 2020	0
Balance at Jun. 30, 2020	$ 0
Balance (in shares) at Sep. 30, 2020	0
Balance at Sep. 30, 2020	$ 0
Beginning balance (in shares) at Jun. 30, 2020		596,264
Beginning balance at Jun. 30, 2020	1,906,630	$ 6	4,351,557	3,737	(2,448,670)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Release of restricted stock units (in shares)		5,642
Release of restricted stock units	0
Shares repurchased for tax withholdings on release of restricted stock units	(7)		(7)
Issuance of common stock for cash upon exercise of stock options, net (in shares)		13,337
Issuance of common stock for cash upon exercise of stock options, net	32,243		32,243
Share-based compensation	91,632		91,632
Other comprehensive income (loss)	(1,674)			(1,674)
Net loss	(94,220)				(94,220)
Ending balance (in shares) at Sep. 30, 2020		615,243
Ending balance at Sep. 30, 2020	$ 1,934,604	$ 6	$ 4,475,425	$ 2,063	$ (2,542,890)

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities
Net income (loss)	$ (336,164)	$ (1,325,653)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	29,174	19,496
Share-based compensation	234,801	1,265,581
Other	7,268	(3,296)
Changes in assets and liabilities:
Accounts receivable	(25,667)	12,331
Prepaid expenses and other assets	(6,184)	(1,502)
Operating lease right-of-use assets	31,835	21,746
Accounts payable	7,689	8,897
Accrued expenses and other liabilities	20,391	13,133
Operating lease liabilities	(35,013)	(19,634)
Net cash used in operating activities	(71,870)	(8,901)
Investing activities
Purchases of property and equipment and intangible assets	(14,032)	(20,433)
Purchases of marketable securities	(808,180)	(527,899)
Sales of marketable securities	174,042	93,389
Maturities of marketable securities	699,133	252,164
Other investing activities	316	0
Net cash provided by (used in) investing activities	51,279	(202,779)
Financing activities
Proceeds from initial public offering, net of underwriters' discounts and commissions	0	1,573,200
Proceeds from exercise of stock options, net	64,992	744
Shares repurchased for tax withholdings on release of restricted stock units	(56,894)	(424,965)
Payment of deferred offering costs and other financing activities	(1,750)	(11,305)
Net cash provided by financing activities	6,348	1,137,674
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(86)	(182)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(14,329)	925,812
Cash, cash equivalents, and restricted cash, beginning of period	677,743	135,290
Cash, cash equivalents, and restricted cash, end of period	663,414	1,061,102
Supplemental cash flow information
Accrued property and equipment	3,952	7,174
Operating lease right-of-use assets obtained in exchange for operating lease liabilities	$ 14,030	$ 41,399

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Reconciliation of cash, cash equivalents and restricted cash to condensed consolidated balance sheets
Cash and cash equivalents	$ 652,723	$ 1,033,871
Restricted cash included in prepaid expenses and other current assets	1,470	2,409
Restricted cash	9,221	24,822
Total cash, cash equivalents, and restricted cash	$ 663,414	$ 1,061,102

Description of Business and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Description of Business and Summary of Significant Accounting Policies	Description of Business and Summary of Significant Accounting Policies Description of Business Pinterest was incorporated in Delaware in 2008 and is headquartered in San Francisco, California. Pinterest is a visual discovery engine that people around the globe use to find the inspiration to create a life they love. We generate revenue by delivering ads on our website and mobile application. Basis of Presentation and Consolidation We prepared the accompanying condensed consolidated financial statements in accordance with generally accepted accounting principles in the United States ("GAAP"). The condensed consolidated financial statements include the accounts of Pinterest, Inc. and its wholly owned subsidiaries. We have eliminated all intercompany balances and transactions. The condensed consolidated balance sheet as of December 31, 2019 included herein was derived from the audited financial statements as of that date. We have condensed or omitted certain information and notes normally included in complete financial statements prepared in accordance with GAAP. As such, these unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2019, which are included in our Annual Report on Form 10-K. In our opinion, the accompanying condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the results for the interim periods presented, but they are not necessarily indicative of the results of operations to be expected for the year ending December 31, 2020. Reclassifications We have reclassified certain amounts in prior periods to conform with current presentation. Use of Estimates Preparing our condensed consolidated financial statements in conformity with GAAP requires us to make estimates and judgments that affect amounts reported in the condensed consolidated financial statements and accompanying notes. We base these estimates and judgments on historical experience and various other assumptions that we consider reasonable. GAAP requires us to make estimates and assumptions in several areas, including the fair values of financial instruments, assets acquired and liabilities assumed through business combinations, common stock prior to our initial public offering ("IPO"), share-based awards, and contingencies as well as the collectability of our accounts receivable, the useful lives of our intangible assets and property and equipment, the incremental borrowing rate we use to determine our operating lease liabilities, and revenue recognition, among others. Actual results could differ materially from these estimates and judgments. Many of our estimates require increased judgment due to the significant volatility, uncertainty and economic disruption of the recent global COVID-19 pandemic. We continue to monitor the effects of the COVID-19 pandemic, and our estimates and judgments may change materially as new events occur or additional information becomes available to us. Segments We operate as a single operating segment. Our chief operating decision maker is our Chief Executive Officer, who reviews financial information presented on a consolidated basis, accompanied by disaggregated information about our revenue, for purposes of making operating decisions, assessing financial performance and allocating resources. Revenue Recognition We generate revenue by delivering ads on our website and mobile application. We recognize revenue only after transferring control of promised goods or services to customers, which occurs when a user clicks on an ad contracted on a cost per click (“CPC”) basis, views an ad contracted on a cost per thousand impressions (“CPM”) basis or views a video ad contracted on a cost per view ("CPV") basis. We typically bill customers on a CPC, CPM or CPV basis, and our payment terms vary by customer type and location. The term between billing and payment due dates is not significant. We occasionally offer customers free ad inventory, and revenue is recognized only after satisfying our contractual performance obligations. When contracts with our customers contain multiple performance obligations, we allocate the overall transaction price, which is the amount of consideration to which we expect to be entitled in exchange for promised goods or services, to each of the distinct performance obligations based on their relative standalone selling prices. We generally determine standalone selling prices based on the effective price charged per contracted click, impression or view and we do not disclose the value of unsatisfied performance obligations because the original expected duration of our contracts is generally less than one year. We record sales commissions in sales and marketing expense as incurred because we would amortize these over a period of less than one year. Deferred revenue was not material as of September 30, 2020 and December 31, 2019. Share-Based Compensation Restricted stock units ("RSUs") granted under our 2009 Stock Plan (the "2009 Plan") are subject to both a service condition, which is typically satisfied over four years, and a performance condition, which was deemed satisfied upon the pricing of our IPO. We did not record any share-based compensation expense for our RSUs prior to our IPO because the performance condition had not yet been satisfied. Upon pricing our IPO, we recorded cumulative share-based compensation expense using the accelerated attribution method for those RSUs granted under our 2009 Plan for which the service condition had been satisfied at that date. We will record the remaining unrecognized share-based compensation expense over the remainder of the requisite service period. RSUs and Restricted Stock Awards ("RSAs") granted under our 2019 Omnibus Incentive Plan (the "2019 Plan") are subject only to a service condition, which is typically satisfied over four years. We record share-based compensation expense for these RSUs and RSAs on a straight-line basis over the requisite service period. We measure RSUs and RSAs based on the fair market value of our common stock on the grant date, and we account for forfeitures as they occur. Leases and Operating Lease Incremental Borrowing Rate We lease office space under operating leases with expiration dates through 2033. We determine whether an arrangement constitutes a lease and record lease liabilities and right-of-use assets on our condensed consolidated balance sheets at lease commencement. We measure lease liabilities based on the present value of the total lease payments not yet paid discounted based on the more readily determinable of the rate implicit in the lease or our incremental borrowing rate, which is the estimated rate we would be required to pay for a collateralized borrowing equal to the total lease payments over the term of the lease. We estimate our incremental borrowing rate based on an analysis of publicly traded debt securities of companies with credit and financial profiles similar to our own. We measure right-of-use assets based on the corresponding lease liability adjusted for (i) payments made to the lessor at or before the commencement date, (ii) initial direct costs we incur and (iii) tenant incentives under the lease. We begin recognizing rent expense when the lessor makes the underlying asset available to us, we do not assume renewals or early terminations unless we are reasonably certain to exercise these options at commencement, and we do not allocate consideration between lease and non-lease components. For short-term leases, we record rent expense in our condensed consolidated statements of operations on a straight-line basis over the lease term and record variable lease payments as incurred. Recently Adopted Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the measurement and recognition of expected credit losses for financial assets not held at fair value. ASU 2016-13 replaces the existing incurred loss impairment model with a forward-looking expected credit loss model which will result in earlier recognition of credit losses. We adopted ASU 2016-13 as of January 1, 2020, using the modified retrospective method, and while the effects of adoption on our condensed consolidated financial statements were not material, we continue to monitor the effects of the COVID-19 pandemic on expected credit losses. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes by removing certain exceptions to the general principles for income taxes. We elected to early adopt ASU 2019-12 effective as of January 1, 2020, and the effects of adoption on our condensed consolidated financial statements were not material.

Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

The fair values of the financial instruments we measure at fair value on a recurring basis are as follows (in thousands):


	September 30, 2020
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	316,736	$	—	$	—	$	316,736
Commercial paper	—		78,479		—		78,479
Certificates of deposit	—		12,010		—		12,010
Corporate bonds	—		3,347		—		3,347

Marketable securities:
Corporate bonds	—		415,998		—		415,998
U.S. treasury securities	271,930		—		—		271,930
Commercial paper	—		169,619		—		169,619
Certificates of deposit	—		73,213		—		73,213
Asset-backed securities	—		33,655		—		33,655
U.S. agency bonds	—		15,992		—		15,992
Non-U.S. government and supranational bonds	—		15,985		—		15,985
Prepaid expenses and other current assets:
Certificates of deposit	—		1,470		—		1,470
Restricted cash:
Certificates of deposit	$	—	$	9,221	$	—	$	9,221


	December 31, 2019
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	214,413	$	—	$	—	$	214,413
Commercial paper	—		105,354		—		105,354
Corporate bonds	—		3,791		—		3,791
Certificates of deposit	—		2,914		—		2,914

Marketable securities:
Corporate bonds	—		450,433		—		450,433
U.S. treasury securities	201,640		—		—		201,640
Commercial paper	—		196,328		—		196,328
Asset-backed securities	—		114,599		—		114,599
Certificates of deposit	—		100,679		—		100,679

Prepaid expenses and other current assets:
Certificates of deposit	—		2,738		—		2,738
Restricted cash:
Certificates of deposit	$	—	$	25,339	$	—	$	25,339

We classify our marketable securities within Level 1 or Level 2 because we determine their fair values using quoted market prices or alternative pricing sources and models utilizing market observable inputs.

Gross unrealized gains and losses on our marketable securities were immaterial in the aggregate as of September 30, 2020 and December 31, 2019. We evaluated all available evidence and did not recognize any allowance for credit losses for our marketable securities as of September 30, 2020 and December 31, 2019. We continue to monitor the effects of the COVID-19 pandemic on expected credit losses.

The fair value of our marketable securities by contractual maturity is as follows (in thousands):


	September 30, 2020
Due in one year or less	$	731,474
Due after one to five years	264,918
Total	$	996,392

Net realized gains and losses from sales of available-for-sale securities were not material for any period presented.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments In March 2019, we entered into a lease for approximately 490,000 square feet of office space to be constructed near our current headquarters campus in San Francisco, California. In August 2020, we entered into an agreement to terminate the lease which involved a one-time payment of $89.5 million. As a result of the termination, we will not be subject to future total minimum lease payments of approximately $440.0 million. Legal Matters We are involved in various lawsuits, claims and proceedings that arise in the ordinary course of business. While the results of legal matters are inherently uncertain, we do not believe the ultimate resolution of these matters, either individually or in aggregate, will have a material adverse effect on our business, financial position, results of operations or cash flows. Letters of Credit We had $8.1 million and $25.5 million of secured letters of credit outstanding as of September 30, 2020 and December 31, 2019. These primarily relate to our office space leases and are fully collateralized by certificates of deposit which we record in prepaid expenses and other current assets or restricted cash in our condensed consolidated balance sheets based on the term of the remaining restriction.

Share-Based Compensation

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Share-Based Compensation

Equity Incentive Plan

In June 2009, our board of directors adopted and approved our 2009 Plan, which provides for the issuance of stock options, RSAs and RSUs to qualified employees, directors and consultants. Stock options granted under our 2009 Stock Plan have a maximum life of 10 years and an exercise price not less than 100% of the fair market value of our common stock on the date of grant. RSUs granted under our 2009 Plan have a maximum life of seven years. No shares of our common stock were reserved for future issuance under our 2009 Plan as of September 30, 2020.

Our 2019 Plan became effective upon closing of our IPO and succeeds our 2009 Plan. Our 2019 Plan provides for the issuance of stock options, RSAs, RSUs and other equity- or cash-based awards to qualified employees, directors and consultants. Stock options granted under our 2019 Plan have a maximum life of 10 years and an exercise price not less than 100% of the fair market value of our common stock on the date of grant. 100,443,058 shares of our Class A common stock were reserved for future issuance under our 2019 Plan as of September 30, 2020.

The number of shares of our Class A common stock available for issuance under the 2019 Plan will be increased by the number of shares of our Class B common stock subject to awards outstanding under our 2009 Plan as of the closing of our IPO that would, but for the terms of the 2019 Plan, have returned to the share reserves of the 2009 Plan pursuant to the terms of such awards, including as the result of forfeiture, repurchase, expiration or retention by us in order to satisfy an award’s exercise price or tax withholding obligations. In addition, the number of shares of our Class A common stock reserved for issuance under our 2019 Plan will automatically increase on the first day of each fiscal year, commencing on January 1, 2020 and ending on (and including) January 1, 2029, in an amount equal to 5% of the total number of shares of our Class A common stock and our Class B common stock outstanding on the last day of the calendar month before the date of each automatic increase, or a lesser number of shares determined by our board of directors.

Stock Option Activity

Stock option activity during the nine months ended September 30, 2020, was as follows (in thousands, except per share amounts):


	Stock Options Outstanding
	Shares	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term	Aggregate Intrinsic Value (1)
				(in years)
Outstanding as of December 31, 2019	56,966	$	2.25	3.5	$	933,299
Granted	1,130	22.35
Exercised	(28,855)	2.25

Outstanding as of September 30, 2020	29,241	$	3.03	3.1	$	1,124,964
Exercisable as of September 30, 2020	28,322	$	2.41	2.9	$	1,107,358

(1)We calculate intrinsic value based on the difference between the exercise price of in-the-money-stock options and the fair value of our common stock as of the respective balance sheet date.

The total grant-date fair value of stock options vested during the nine months ended September 30, 2020 and 2019, was $2.5 million and $2.1 million, respectively. The aggregate intrinsic value of stock options exercised during the nine months ended September 30, 2020 and 2019, was $719 million and $5.8 million, respectively.

The total grant-date fair value of stock options granted during the nine months ended September 30, 2020 was not material. No stock options were granted during the nine months ended September 30, 2019.

Restricted Stock Unit and Restricted Stock Award Activity

RSU and RSA activity during the nine months ended September 30, 2020, was as follows (in thousands, except per share amounts):


	Restricted Stock Units and Restricted Stock Awards Outstanding
	Shares	Weighted Average Grant Date Fair Value
Outstanding as of December 31, 2019	56,791	$	20.19
Granted	29,060	17.99
Released	(17,105)	19.39
Forfeited	(9,111)	18.82
Outstanding as of September 30, 2020	59,635	$	19.55

Share-Based Compensation

Share-based compensation expense during the three and nine months ended September 30, 2020 and 2019, was as follows (in thousands):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Cost of revenue	$	2,298	$	1,568	$	6,049	$	29,740
Research and development	61,357		83,539		156,621		794,161
Sales and marketing	11,958		21,243		23,803		223,400
General and administrative	16,019		23,938		48,328		218,280
Total share-based compensation	$	91,632	$	130,288	$	234,801	$	1,265,581

As of September 30, 2020, we had $764.3 million of unrecognized share-based compensation expense, which we expect to recognize over a weighted-average period of 3.1 years.

Net Loss Per Share Attributable to Common Stockholders

9 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Net Loss Per Share Attributable to Common Stockholders

We present net loss per share attributable to common stockholders using the two-class method required for multiple classes of common stock and participating securities. Holders of our Class A and Class B common stock have identical rights except with respect to voting, conversion and transfer rights and therefore share equally in our net losses. Prior to our IPO, we considered all series of our redeemable convertible preferred stock participating securities. We have not allocated net loss attributable to common stockholders to our redeemable convertible preferred stock because the holders of our redeemable convertible preferred stock are not contractually obligated to share in our losses.

We calculate basic net loss per share attributable to common stockholders by dividing net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share attributable to common stockholders gives effect to all potential shares of common stock, including common stock issuable upon conversion of our redeemable convertible preferred stock and redeemable convertible preferred stock warrants, stock options, RSAs, RSUs and common stock warrants to the extent these are dilutive.

We calculated basic and diluted net loss per share attributable to common stockholders as follows (in thousands, except per share amounts):


	Three Months Ended September 30,								Nine Months Ended September 30,
	2020				2019				2020				2019
	Class A		Class B		Class A		Class B		Class A		Class B		Class A		Class B
Numerator:
Net loss attributable to common stockholders	$	(75,035)	$	(19,185)	$	(38,702)	$	(86,030)	$	(242,731)	$	(93,433)	$	(336,971)	$	(988,682)
Denominator:
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted	480,606		122,885		169,452		376,674		425,218		163,677		81,212		238,278
Net loss per share attributable to common stockholders, basic and diluted	$	(0.16)	$	(0.16)	$	(0.23)	$	(0.23)	$	(0.57)	$	(0.57)	$	(4.15)	$	(4.15)

Basic net loss per share is the same as diluted net loss per share because we reported net losses for all periods presented. We excluded the following weighted-average potential shares of common stock from our calculation of diluted net loss per share attributable to common stockholders because these would be anti-dilutive (in thousands):


	Three Months Ended September 30,		Nine Months Ended September 30,
	2020	2019	2020	2019
Redeemable convertible preferred stock	—	—	—	127,642
Outstanding stock options	35,226	76,334	44,659	76,447
Unvested restricted stock units and restricted stock awards	63,695	63,738	64,353	72,961
Redeemable convertible preferred stock warrants	—	—	—	103


Total	98,921	140,072	109,013	277,153

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We determine our income tax provision for interim periods using an estimate of our annual effective tax rate adjusted for discrete items occurring during the periods presented. The primary difference between our effective tax rate and the federal statutory rate is the full valuation allowance we have established on our federal, state and foreign net operating losses and credits. Income taxes from international operations are not material for the three and nine months ended September 30, 2020 and 2019. On June 7, 2019, a three-judge panel from the U.S. Court of Appeals for the Ninth Circuit overturned the U.S. Tax Court's decision in Altera Corp. v. Commissioner and upheld the portion of the Treasury regulations under Section 482 of the Internal Revenue Code that requires related parties in a cost-sharing arrangement to share expenses related to share-based compensation. As a result of this decision, our gross unrecognized tax benefits increased to reflect the impact of including share-based compensation in cost-sharing arrangements. Recognizing our gross unrecognized tax benefits would not affect our effective tax rate as their recognition would be offset by the reversal of the related deferred tax assets, which are subject to a full valuation allowance. On July 22, 2019, the taxpayer filed a petition for a rehearing before the full Ninth Circuit and the request was denied on November 12, 2019. On February 10, 2020, the taxpayer filed a petition to appeal the decision to the Supreme Court and on June 22, 2020, the Supreme Court denied the petition. As a result of the Supreme Court’s action, our U.S. deferred tax asset related to net operating losses was reduced by $24.4 million and we no longer consider this to be an uncertain tax position. There is no impact on our effective tax rate for the three and nine months ended September 30, 2020, due to our full valuation allowance against our deferred tax assets.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Geographical Information

9 Months Ended

Sep. 30, 2020

Segment Reporting [Abstract]

Geographical Information

Revenue disaggregated by geography based on our customers’ billing addresses is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
United States	$	367,998	$	247,222	$	827,220	$	660,754
International(1)	$	74,618	32,481		159,821		82,109
Total revenue	$	442,616	$	279,703	$	987,041	$	742,863

(1)No individual country other than the United States exceeded 10% of our total revenue for any period presented.

Property and equipment, net and operating lease right-of-use assets by geography is as follows (in thousands):


	September 30,		December 31,
	2020		2019
United States	$	227,517	$	266,763
International(1)	13,580		13,480
Total property and equipment, net and operating lease right-of-use assets	$	241,097	$	280,243

(1)No individual country other than the United States exceeded 10% of our total property and equipment, net and operating lease right-of-use assets for any period presented.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details

Description of Business and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Basis of Presentation	We prepared the accompanying condensed consolidated financial statements in accordance with generally accepted accounting principles in the United States ("GAAP"). The condensed consolidated financial statements include the accounts of Pinterest, Inc. and its wholly owned subsidiaries. We have eliminated all intercompany balances and transactions. The condensed consolidated balance sheet as of December 31, 2019 included herein was derived from the audited financial statements as of that date. We have condensed or omitted certain information and notes normally included in complete financial statements prepared in accordance with GAAP. As such, these unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2019, which are included in our Annual Report on Form 10-K. In our opinion, the accompanying condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the results for the interim periods presented, but they are not necessarily indicative of the results of operations to be expected for the year ending December 31, 2020.
Consolidation	We prepared the accompanying condensed consolidated financial statements in accordance with generally accepted accounting principles in the United States ("GAAP"). The condensed consolidated financial statements include the accounts of Pinterest, Inc. and its wholly owned subsidiaries. We have eliminated all intercompany balances and transactions. The condensed consolidated balance sheet as of December 31, 2019 included herein was derived from the audited financial statements as of that date. We have condensed or omitted certain information and notes normally included in complete financial statements prepared in accordance with GAAP. As such, these unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2019, which are included in our Annual Report on Form 10-K. In our opinion, the accompanying condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the results for the interim periods presented, but they are not necessarily indicative of the results of operations to be expected for the year ending December 31, 2020.
Reclassifications	We have reclassified certain amounts in prior periods to conform with current presentation.
Use of Estimates	Preparing our condensed consolidated financial statements in conformity with GAAP requires us to make estimates and judgments that affect amounts reported in the condensed consolidated financial statements and accompanying notes. We base these estimates and judgments on historical experience and various other assumptions that we consider reasonable. GAAP requires us to make estimates and assumptions in several areas, including the fair values of financial instruments, assets acquired and liabilities assumed through business combinations, common stock prior to our initial public offering ("IPO"), share-based awards, and contingencies as well as the collectability of our accounts receivable, the useful lives of our intangible assets and property and equipment, the incremental borrowing rate we use to determine our operating lease liabilities, and revenue recognition, among others. Actual results could differ materially from these estimates and judgments. Many of our estimates require increased judgment due to the significant volatility, uncertainty and economic disruption of the recent global COVID-19 pandemic. We continue to monitor the effects of the COVID-19 pandemic, and our estimates and judgments may change materially as new events occur or additional information becomes available to us.
Segments	We operate as a single operating segment. Our chief operating decision maker is our Chief Executive Officer, who reviews financial information presented on a consolidated basis, accompanied by disaggregated information about our revenue, for purposes of making operating decisions, assessing financial performance and allocating resources.
Revenue Recognition	We generate revenue by delivering ads on our website and mobile application. We recognize revenue only after transferring control of promised goods or services to customers, which occurs when a user clicks on an ad contracted on a cost per click (“CPC”) basis, views an ad contracted on a cost per thousand impressions (“CPM”) basis or views a video ad contracted on a cost per view ("CPV") basis. We typically bill customers on a CPC, CPM or CPV basis, and our payment terms vary by customer type and location. The term between billing and payment due dates is not significant. We occasionally offer customers free ad inventory, and revenue is recognized only after satisfying our contractual performance obligations. When contracts with our customers contain multiple performance obligations, we allocate the overall transaction price, which is the amount of consideration to which we expect to be entitled in exchange for promised goods or services, to each of the distinct performance obligations based on their relative standalone selling prices. We generally determine standalone selling prices based on the effective price charged per contracted click, impression or view and we do not disclose the value of unsatisfied performance obligations because the original expected duration of our contracts is generally less than one year. We record sales commissions in sales and marketing expense as incurred because we would amortize these over a period of less than one year.
Share-Based Compensation	Restricted stock units ("RSUs") granted under our 2009 Stock Plan (the "2009 Plan") are subject to both a service condition, which is typically satisfied over four years, and a performance condition, which was deemed satisfied upon the pricing of our IPO. We did not record any share-based compensation expense for our RSUs prior to our IPO because the performance condition had not yet been satisfied. Upon pricing our IPO, we recorded cumulative share-based compensation expense using the accelerated attribution method for those RSUs granted under our 2009 Plan for which the service condition had been satisfied at that date. We will record the remaining unrecognized share-based compensation expense over the remainder of the requisite service period. RSUs and Restricted Stock Awards ("RSAs") granted under our 2019 Omnibus Incentive Plan (the "2019 Plan") are subject only to a service condition, which is typically satisfied over four years. We record share-based compensation expense for these RSUs and RSAs on a straight-line basis over the requisite service period. We measure RSUs and RSAs based on the fair market value of our common stock on the grant date, and we account for forfeitures as they occur.
Leases and Operating Lease Incremental Borrowing Rate	We lease office space under operating leases with expiration dates through 2033. We determine whether an arrangement constitutes a lease and record lease liabilities and right-of-use assets on our condensed consolidated balance sheets at lease commencement. We measure lease liabilities based on the present value of the total lease payments not yet paid discounted based on the more readily determinable of the rate implicit in the lease or our incremental borrowing rate, which is the estimated rate we would be required to pay for a collateralized borrowing equal to the total lease payments over the term of the lease. We estimate our incremental borrowing rate based on an analysis of publicly traded debt securities of companies with credit and financial profiles similar to our own. We measure right-of-use assets based on the corresponding lease liability adjusted for (i) payments made to the lessor at or before the commencement date, (ii) initial direct costs we incur and (iii) tenant incentives under the lease. We begin recognizing rent expense when the lessor makes the underlying asset available to us, we do not assume renewals or early terminations unless we are reasonably certain to exercise these options at commencement, and we do not allocate consideration between lease and non-lease components. For short-term leases, we record rent expense in our condensed consolidated statements of operations on a straight-line basis over the lease term and record variable lease payments as incurred.
Recently Adopted Accounting Pronouncement	In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the measurement and recognition of expected credit losses for financial assets not held at fair value. ASU 2016-13 replaces the existing incurred loss impairment model with a forward-looking expected credit loss model which will result in earlier recognition of credit losses. We adopted ASU 2016-13 as of January 1, 2020, using the modified retrospective method, and while the effects of adoption on our condensed consolidated financial statements were not material, we continue to monitor the effects of the COVID-19 pandemic on expected credit losses. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes by removing certain exceptions to the general principles for income taxes. We elected to early adopt ASU 2019-12 effective as of January 1, 2020, and the effects of adoption on our condensed consolidated financial statements were not material.

Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Fair Values of Financial Instruments Measured on a Recurring Basis

The fair values of the financial instruments we measure at fair value on a recurring basis are as follows (in thousands):


	September 30, 2020
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	316,736	$	—	$	—	$	316,736
Commercial paper	—		78,479		—		78,479
Certificates of deposit	—		12,010		—		12,010
Corporate bonds	—		3,347		—		3,347

Marketable securities:
Corporate bonds	—		415,998		—		415,998
U.S. treasury securities	271,930		—		—		271,930
Commercial paper	—		169,619		—		169,619
Certificates of deposit	—		73,213		—		73,213
Asset-backed securities	—		33,655		—		33,655
U.S. agency bonds	—		15,992		—		15,992
Non-U.S. government and supranational bonds	—		15,985		—		15,985
Prepaid expenses and other current assets:
Certificates of deposit	—		1,470		—		1,470
Restricted cash:
Certificates of deposit	$	—	$	9,221	$	—	$	9,221


	December 31, 2019
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	214,413	$	—	$	—	$	214,413
Commercial paper	—		105,354		—		105,354
Corporate bonds	—		3,791		—		3,791
Certificates of deposit	—		2,914		—		2,914

Marketable securities:
Corporate bonds	—		450,433		—		450,433
U.S. treasury securities	201,640		—		—		201,640
Commercial paper	—		196,328		—		196,328
Asset-backed securities	—		114,599		—		114,599
Certificates of deposit	—		100,679		—		100,679

Prepaid expenses and other current assets:
Certificates of deposit	—		2,738		—		2,738
Restricted cash:
Certificates of deposit	$	—	$	25,339	$	—	$	25,339

Fair Value of Marketable Securities by Contractual Maturity

The fair value of our marketable securities by contractual maturity is as follows (in thousands):


	September 30, 2020
Due in one year or less	$	731,474
Due after one to five years	264,918
Total	$	996,392

Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Stock Option Activity

Stock option activity during the nine months ended September 30, 2020, was as follows (in thousands, except per share amounts):


	Stock Options Outstanding
	Shares	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term	Aggregate Intrinsic Value (1)
				(in years)
Outstanding as of December 31, 2019	56,966	$	2.25	3.5	$	933,299
Granted	1,130	22.35
Exercised	(28,855)	2.25

Outstanding as of September 30, 2020	29,241	$	3.03	3.1	$	1,124,964
Exercisable as of September 30, 2020	28,322	$	2.41	2.9	$	1,107,358

(1)We calculate intrinsic value based on the difference between the exercise price of in-the-money-stock options and the fair value of our common stock as of the respective balance sheet date.

Restricted Stock Unit Activity

RSU and RSA activity during the nine months ended September 30, 2020, was as follows (in thousands, except per share amounts):


	Restricted Stock Units and Restricted Stock Awards Outstanding
	Shares	Weighted Average Grant Date Fair Value
Outstanding as of December 31, 2019	56,791	$	20.19
Granted	29,060	17.99
Released	(17,105)	19.39
Forfeited	(9,111)	18.82
Outstanding as of September 30, 2020	59,635	$	19.55

Share-Based Compensation Expense

Share-based compensation expense during the three and nine months ended September 30, 2020 and 2019, was as follows (in thousands):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Cost of revenue	$	2,298	$	1,568	$	6,049	$	29,740
Research and development	61,357		83,539		156,621		794,161
Sales and marketing	11,958		21,243		23,803		223,400
General and administrative	16,019		23,938		48,328		218,280
Total share-based compensation	$	91,632	$	130,288	$	234,801	$	1,265,581

Net Loss Per Share Attributable to Common Stockholders (Tables)

9 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Calculation of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders

We calculated basic and diluted net loss per share attributable to common stockholders as follows (in thousands, except per share amounts):


	Three Months Ended September 30,								Nine Months Ended September 30,
	2020				2019				2020				2019
	Class A		Class B		Class A		Class B		Class A		Class B		Class A		Class B
Numerator:
Net loss attributable to common stockholders	$	(75,035)	$	(19,185)	$	(38,702)	$	(86,030)	$	(242,731)	$	(93,433)	$	(336,971)	$	(988,682)
Denominator:
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted	480,606		122,885		169,452		376,674		425,218		163,677		81,212		238,278
Net loss per share attributable to common stockholders, basic and diluted	$	(0.16)	$	(0.16)	$	(0.23)	$	(0.23)	$	(0.57)	$	(0.57)	$	(4.15)	$	(4.15)

Weighted-Average Anti-Dilutive Shares of Common Stock Excluded from the Calculation of Diluted Net Loss Per Share

Basic net loss per share is the same as diluted net loss per share because we reported net losses for all periods presented. We excluded the following weighted-average potential shares of common stock from our calculation of diluted net loss per share attributable to common stockholders because these would be anti-dilutive (in thousands):


	Three Months Ended September 30,		Nine Months Ended September 30,
	2020	2019	2020	2019
Redeemable convertible preferred stock	—	—	—	127,642
Outstanding stock options	35,226	76,334	44,659	76,447
Unvested restricted stock units and restricted stock awards	63,695	63,738	64,353	72,961
Redeemable convertible preferred stock warrants	—	—	—	103


Total	98,921	140,072	109,013	277,153

Geographical Information (Tables)

9 Months Ended

Sep. 30, 2020

Segment Reporting [Abstract]

Revenue Disaggregated by Geography

Revenue disaggregated by geography based on our customers’ billing addresses is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
United States	$	367,998	$	247,222	$	827,220	$	660,754
International(1)	$	74,618	32,481		159,821		82,109
Total revenue	$	442,616	$	279,703	$	987,041	$	742,863

(1)No individual country other than the United States exceeded 10% of our total revenue for any period presented.

Property and Equipment, Net and Operating Lease Right-of-Use Assets by Geography

Property and equipment, net and operating lease right-of-use assets by geography is as follows (in thousands):


	September 30,		December 31,
	2020		2019
United States	$	227,517	$	266,763
International(1)	13,580		13,480
Total property and equipment, net and operating lease right-of-use assets	$	241,097	$	280,243

(1)No individual country other than the United States exceeded 10% of our total property and equipment, net and operating lease right-of-use assets for any period presented.

Description of Business and Summary of Significant Accounting Policies (Details)	9 Months Ended
	Sep. 30, 2020 segment
Summary of Significant Accounting Policies [Line Items]
Number of operating segments	1
RSUs \| 2009 Plan
Summary of Significant Accounting Policies [Line Items]
Service period	4 years
Unvested restricted stock units and restricted stock awards \| 2019 Plan
Summary of Significant Accounting Policies [Line Items]
Service period	4 years

Fair Value of Financial Instruments - Fair Values of Financial Instruments Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 996,392
Corporate bonds \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	415,998	$ 450,433
Corporate bonds \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Corporate bonds \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	415,998	450,433
Corporate bonds \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
U.S. treasury securities \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	271,930	201,640
U.S. treasury securities \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	271,930	201,640
U.S. treasury securities \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
U.S. treasury securities \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Commercial paper \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	169,619	196,328
Commercial paper \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Commercial paper \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	169,619	196,328
Commercial paper \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Certificates of deposit \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	73,213	100,679
Prepaid expenses and other current assets	1,470	2,738
Restricted cash	9,221	25,339
Certificates of deposit \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Prepaid expenses and other current assets	0	0
Restricted cash	0	0
Certificates of deposit \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	73,213	100,679
Prepaid expenses and other current assets	1,470	2,738
Restricted cash	9,221	25,339
Certificates of deposit \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Prepaid expenses and other current assets	0	0
Restricted cash	0	0
Asset-backed securities \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	33,655	114,599
Asset-backed securities \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
Asset-backed securities \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	33,655	114,599
Asset-backed securities \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0	0
U.S. agency bonds \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15,992
U.S. agency bonds \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0
U.S. agency bonds \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15,992
U.S. agency bonds \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0
Non-U.S. government and supranational bonds \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15,985
Non-U.S. government and supranational bonds \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0
Non-U.S. government and supranational bonds \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	15,985
Non-U.S. government and supranational bonds \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	0
Money market funds \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	316,736	214,413
Money market funds \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	316,736	214,413
Money market funds \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Money market funds \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Commercial paper \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	78,479	105,354
Commercial paper \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Commercial paper \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	78,479	105,354
Commercial paper \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Certificates of deposit \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	12,010	2,914
Certificates of deposit \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Certificates of deposit \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	12,010	2,914
Certificates of deposit \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Corporate bonds \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	3,347	3,791
Corporate bonds \| Recurring \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Corporate bonds \| Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	3,347	3,791
Corporate bonds \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 0	$ 0

Fair Value of Financial Instruments - Fair Value of Marketable Securities by Contractual Maturity (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Cash and Cash Equivalents [Abstract]
Due in one year or less	$ 731,474
Due after one to five years	264,918
Total	$ 996,392

Commitments and Contingencies (Details) ft² in Thousands, $ in Millions	1 Months Ended
	Aug. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($) ft²
Commitments and Contingencies Disclosure [Abstract]
Area of office space (in sqft) \| ft²				490
One-time payment for lease termination	$ 89.5
Noncancelable minimum lease payments not yet commenced				$ 440.0
Secured letters of credit outstanding		$ 8.1	$ 25.5

Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant-date fair value of stock options vested	$ 2.5	$ 2.1
Aggregate intrinsic value of stock options exercised	$ 719.0	$ 5.8
Stock options granted (in shares)	1,130,000	0
Unrecognized share-based compensation expense	$ 764.3
Weighted-average recognition period for unrecognized share-based compensation expense	3 years 1 month 6 days
2009 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	0
2009 Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
2009 Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	7 years
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares, additional reserve	5.00%
2019 Plan \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)	100,443,058
2019 Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years

Share-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Shares
Beginning balance (in shares)	56,966,000
Granted (in shares)	1,130,000	0
Exercised (in shares)	(28,855,000)
Ending balance (in shares)	29,241,000
Exercisable (in shares)	28,322,000
Weighted-Average Exercise Price
Beginning balance (in dollars per share)	$ 2.25
Granted (in dollars per share)	22.35
Exercised (in dollars per share)	2.25
Ending balance (in dollars per share)	3.03
Exercisable (in dollars per share)	$ 2.41
Weighted-Average Remaining Contractual Term, Outstanding	3 years 1 month 6 days	3 years 6 months
Weighted-Average Remaining Contractual Term, Exercisable	2 years 10 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 1,124,964		$ 933,299
Aggregate Intrinsic Value, Exercisable	$ 1,107,358

Share-Based Compensation - Restricted Stock Unit Activity (Details) - Restricted Stock Units and Restricted Stock Awards Outstanding shares in Thousands	9 Months Ended
	Sep. 30, 2020 $ / shares shares
Shares
Beginning balance (in shares) \| shares	56,791
Granted (in shares) \| shares	29,060
Released (in shares) \| shares	(17,105)
Forfeited (in shares) \| shares	(9,111)
Ending balance (in shares) \| shares	59,635
Weighted Average Grant Date Fair Value
Beginning balance (in dollars per share) \| $ / shares	$ 20.19
Granted (in dollars per share) \| $ / shares	17.99
Released (in dollars per share) \| $ / shares	19.39
Forfeited (in dollars per share) \| $ / shares	18.82
Ending balance (in dollars per share) \| $ / shares	$ 19.55

Share-Based Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	$ 91,632	$ 130,288	$ 234,801	$ 1,265,581
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	2,298	1,568	6,049	29,740
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	61,357	83,539	156,621	794,161
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	11,958	21,243	23,803	223,400
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation	$ 16,019	$ 23,938	$ 48,328	$ 218,280

Net Loss Per Share Attributable to Common Stockholders - Calculation of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Numerator:
Net loss attributable to common stockholders	$ (94,220)	$ (124,732)	$ (336,164)	$ (1,325,653)
Denominator:
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted (in shares)	603,490	546,126	588,895	319,490
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.16)	$ (0.23)	$ (0.57)	$ (4.15)
Class A
Numerator:
Net loss attributable to common stockholders	$ (75,035)	$ (38,702)	$ (242,731)	$ (336,971)
Denominator:
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted (in shares)	480,606	169,452	425,218	81,212
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.16)	$ (0.23)	$ (0.57)	$ (4.15)
Class B
Numerator:
Net loss attributable to common stockholders	$ (19,185)	$ (86,030)	$ (93,433)	$ (988,682)
Denominator:
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted (in shares)	122,885	376,674	163,677	238,278
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.16)	$ (0.23)	$ (0.57)	$ (4.15)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669619-108580

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Net Loss Per Share Attributable to Common Stockholders - Weighted-Average Anti-Dilutive Shares of Common Stock Excluded from the Calculation of Diluted Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average anti-dilutive shares of common stock (in shares)	98,921	140,072	109,013	277,153
Redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average anti-dilutive shares of common stock (in shares)	0	0	0	127,642
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average anti-dilutive shares of common stock (in shares)	35,226	76,334	44,659	76,447
Unvested restricted stock units and restricted stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average anti-dilutive shares of common stock (in shares)	63,695	63,738	64,353	72,961
Redeemable convertible preferred stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average anti-dilutive shares of common stock (in shares)	0	0	0	103

Income Taxes (Details) $ in Millions	Jun. 22, 2020 USD ($)
Income Tax Disclosure [Abstract]
Reduction in deferred tax assets related to net operating losses	$ 24.4

Geographical Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Geographical Information (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 442,616	$ 279,703	$ 987,041	$ 742,863
Total property and equipment, net and operating lease right-of-use assets	241,097		241,097		$ 280,243
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	367,998	247,222	827,220	660,754
Total property and equipment, net and operating lease right-of-use assets	227,517		227,517		266,763
International
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	74,618	$ 32,481	159,821	$ 82,109
Total property and equipment, net and operating lease right-of-use assets	$ 13,580		$ 13,580		$ 13,480

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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