Dropbox (DBX) 10-Q 8 May 20 2020 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2020	May 04, 2020
Class of Stock [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-38434
Entity Registrant Name	Dropbox, Inc.
Entity Central Index Key	0001467623
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-0138832
Entity Address, Address Line One	1800 Owens Street
Entity Address, City or Town	San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94158
City Area Code	415
Local Phone Number	857-6800
Title of 12(b) Security	Class A Common Stock, par value $0.00001 per share
Trading Symbol	DBX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Class A common stock
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		262,947,182
Class B common stock
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		150,266,636
Class C common stock
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 486.4	$ 551.3
Short-term investments	614.4	607.7
Trade and other receivables, net	36.9	36.7
Prepaid expenses and other current assets	57.5	47.5
Total current assets	1,195.2	1,243.2
Property and equipment, net	473.2	445.3
Operating lease right-of-use asset	708.1	657.9
Intangible assets, net	44.4	47.4
Goodwill	233.3	234.5
Other assets	63.1	70.9
Total assets	2,717.3	2,699.2
Current liabilities:
Accounts payable	38.8	40.7
Accrued and other current liabilities	149.5	161.9
Accrued compensation and benefits	41.4	101.4
Operating lease liability	84.3	79.9
Finance lease obligation	80	76.7
Deferred revenue	576.8	554.2
Total current liabilities	970.8	1,014.8
Operating lease liability, non-current	771.6	711.9
Finance lease obligation, non-current	147.9
Finance lease obligation, non-current		138.2
Other non-current liabilities	26.6	25.9
Total liabilities	1,916.9	1,890.8
Commitments and contingencies (Note 10)
Stockholders’ equity:
Additional paid-in capital	2,528.5	2,531.3
Accumulated deficit	(1,726.6)	(1,726.2)
Accumulated other comprehensive income (loss)	(1.5)	3.3
Total stockholders’ equity	800.4	808.4
Total liabilities and stockholders’ equity	$ 2,717.3	$ 2,699.2

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue		$ 455	$ 385.6
Cost of revenue	[1]	103.1	98.4
Gross profit		351.9	287.2
Operating expenses
Research and development	[1]	181.8	150
Sales and marketing	[1]	104.3	101.5
General and administrative(2)	[1],[2]	39	57
Total operating expenses	[1]	325.1	308.5
Income (loss) from operations		26.8	(21.3)
Interest income, net		2.4	3.7
Other income, net		10.6	4.2
Income (loss) before income taxes		39.8	(13.4)
Benefit from (provision for) income taxes		(0.5)	5.7
Net income (loss)		$ 39.3	$ (7.7)
Net income (loss) per share attributable to common stockholders, basic (in dollars per share)		$ 0.09	$ (0.02)
Net income (loss) per share attributable to common stockholders, diluted (in dollars per share)		$ 0.09	$ (0.02)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)		417.3	410.5
Weighted-average shares used in computing net loss per share attributable to common stockholders,diluted (in shares)		419.3	410.5
[1]	Includes stock-based compensation as follows (in millions): Three months ended 2020 2019 Cost of revenue $ 3.5 $ 3.0 Research and development 37.2 30.5 Sales and marketing 6.7 7.1 General and administrative (2) (7.6 ) 15.0
[2]	On March 19, 2020, one of the Company's co-founders resigned as a member of the board and as an officer of the Company, resulting in the reversal of $23.8 million in stock-based compensation expense. Of the total amount reversed, $21.5 million

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reversal of stock based compensation expense	$ 23.8
Cost of revenue
Allocated share-based compensation expense	3.5	$ 3
Research and development
Allocated share-based compensation expense	37.2	30.5
Sales and marketing
Allocated share-based compensation expense	6.7	7.1
General and administrative(2)
Allocated share-based compensation expense	$ (7.6)	$ 15

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 39.3	$ (7.7)
Other comprehensive income (loss), net of tax:
Change in foreign currency translation adjustments	(3)	1.1
Change in net unrealized gains (losses), on short-term investments	(1.8)	1.9
Total other comprehensive income (loss), net of tax	(4.8)	3
Comprehensive income (loss)	$ 34.5	$ (4.7)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Class A and Class B common stock	Additional paid-in capital	Accumulated deficit	Accumulated other comprehensive income (loss)
Shares outstanding, beginning of the period (in shares) at Dec. 31, 2018		409.6
Shareholders equity, beginning balance at Dec. 31, 2018	$ 676.8	$ 0	$ 2,337.5	$ (1,659.5)	$ (1.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Release of restricted stock units (in shares)		2.6
Shares repurchased for tax withholdings on release of restricted stock (in shares)		(1)
Shares repurchased for tax withholdings on release of restricted stock	(25.5)		(17)	(8.5)
Exercise of stock options and awards (in shares)		0.2
Exercise of stock options and awards	0.9		0.9
Assumed stock options in connection with acquisition	0.8		0.8
Stock-based compensation	55.6		55.6
Other comprehensive income (loss)	3				3
Net income (loss)	(7.7)
Shares outstanding, end of the period (in shares) at Mar. 31, 2019		411.4
Shareholders equity, ending balance at Mar. 31, 2019	704.9	$ 0	2,377.8	(1,674.7)	1.8
Shares outstanding, beginning of the period (in shares) at Dec. 31, 2019		417
Shareholders equity, beginning balance at Dec. 31, 2019	$ 808.4	$ 0	2,531.3	(1,726.2)	3.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Release of restricted stock units (in shares)		2.7
Shares repurchased for tax withholdings on release of restricted stock (in shares)	(1)	(1)
Shares repurchased for tax withholdings on release of restricted stock	$ (18.9)		(9.3)	(9.6)
Repurchases of common stock (in shares)		(3.7)
Repurchases of common stock	$ (64)		(33.9)	(30.1)
Exercise of stock options and awards (in shares)	0.1	0.1
Exercise of stock options and awards	$ 0.6		0.6
Stock-based compensation	39.8		39.8
Other comprehensive income (loss)	(4.8)				(4.8)
Net income (loss)	39.3
Shares outstanding, end of the period (in shares) at Mar. 31, 2020		415.1
Shareholders equity, ending balance at Mar. 31, 2020	$ 800.4	$ 0	$ 2,528.5	$ (1,726.6)	$ (1.5)

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flow from operating activities
Net income (loss)	$ 39.3	$ (7.7)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	39.5	45.8
Stock-based compensation	39.8	55.6
Net gains on equity investments	(11)	0
Amortization of deferred commissions	5.1	3.9
Other	1.2	(4.4)
Changes in operating assets and liabilities:
Trade and other receivables, net	(1.2)	(5.1)
Prepaid expenses and other current assets	(14.7)	(14.2)
Other assets	17.8	11.2
Accounts payable	(7.8)	(5.2)
Accrued and other current liabilities	(9.9)	10
Accrued compensation and benefits	(59.7)	(45.9)
Deferred revenue	22.2	18.6
Other non-current liabilities	(16.5)	(13.2)
Tenant improvement allowance reimbursement	(9.2)	(13.8)
Net cash provided by operating activities	53.3	63.2
Cash flow from investing activities
Capital expenditures	(27.8)	(29.7)
Business combinations, net of cash acquired	0	(172.1)
Purchases of short-term investments	(120.5)	(153)
Proceeds from sales of short-term investments	65.1	110.2
Proceeds from maturities of short-term investments	67.7	66.6
Other	3.8	4.7
Net cash used in investing activities	(11.7)	(173.3)
Cash flow from financing activities
Shares repurchased for tax withholdings on release of restricted stock	(18.9)	(25.5)
Proceeds from issuance of common stock, net of repurchases	0.7	0.9
Principal payments on finance lease obligations	(21.7)	(26.2)
Common stock repurchases	(64)	0
Other	(0.4)	(0.2)
Net cash used in financing activities	(104.3)	(51)
Effect of exchange rate changes on cash and cash equivalents	(2.2)	1
Change in cash and cash equivalents	(64.9)	(160.1)
Cash and cash equivalents - beginning of period	551.3	519.3
Cash and cash equivalents - end of period	486.4	359.2
Supplemental cash flow data:
Property and equipment acquired under finance leases	$ 34.7	$ 39.9

Description of the Business and

Description of the Business and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business and Summary of Significant Accounting Policies	Description of the Business and Summary of Significant Accounting Policies Business Dropbox, Inc. (the “Company” or “Dropbox”) is the world’s first smart workspace. Dropbox was incorporated in May 2007 as Evenflow, Inc., a Delaware corporation, and changed its name to Dropbox, Inc. in October 2009. The Company is headquartered in San Francisco, California. Basis of presentation and consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the United States of America generally accepted accounting principles (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission ("SEC") regarding interim financial reporting. The accompanying unaudited condensed consolidated financial statements include the accounts of Dropbox and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The condensed consolidated balance sheet as of December 31, 2019 included herein was derived from the audited financial statements as of that date. The unaudited condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the balance sheets, statements of operations, statements of comprehensive income (loss), statements of stockholders' equity and the statements of cash flows for the interim periods, but are not necessarily indicative of the results of operations to be anticipated for the full fiscal year ended December 31, 2020 or any future period. The unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the related notes thereto as of and for the year ended December 31, 2019 , included in the Company's Annual Report on Form 10-K on file with the SEC ("Annual Report"). Use of estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported and disclosed in the Company’s condensed consolidated financial statements and accompanying notes. These estimates are based on information available as of the date of the condensed consolidated financial statements. Management evaluates these estimates and assumptions on a regular basis. Actual results may differ materially from these estimates. The Company’s most significant estimates and judgments involves the valuation of acquired intangible assets and goodwill from business combinations. Financial information about segments and geographic areas The Company manages its operations and allocates resources as a single operating segment. Further, the Company manages, monitors, and reports its financials as a single reporting segment. The Company’s chief operating decision-maker is its Chief Executive Officer, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, assessing financial performance, and allocating resources. See Note 15, "Geographic Areas" for information regarding the Company’s long-lived assets and revenue by geography. Foreign currency transactions The assets and liabilities of the Company’s foreign subsidiaries are translated from their respective functional currencies into U.S. dollars at the exchange rates in effect at the balance sheet date. Revenue and expense amounts are translated at the average exchange rate for the period. Foreign currency translation gains and losses are recorded in other comprehensive income (loss). Gains and losses realized from foreign currency transactions (those transactions denominated in currencies other than the foreign subsidiaries’ functional currency) are included in other income, net. Monetary assets and liabilities are remeasured using foreign currency exchange rates at the end of the period, and non-monetary assets are remeasured based on historical exchange rates. The Company recorded net foreign currency transactions losses of $ 1.2 million and $ 0.1 million during the three months ended March 31, 2020 and 2019, respectively Revenue recognition The Company derives its revenue from subscription fees from customers for access to its platform. The Company’s policy is to exclude sales and other indirect taxes when measuring the transaction price of its subscription agreements. The Company accounts for revenue contracts with customers through the following steps: • Identification of the contract, or contracts, with a customer • Identification of the performance obligations in the contract • Determination of the transaction price • Allocation of the transaction price to the performance obligations in the contract • Recognition of revenue when, or as, the Company satisfies a performance obligation The Company’s subscription agreements generally have monthly or annual contractual terms and a small percentage have multi-year contractual terms. Revenue is recognized ratably over the related contractual term beginning on the date that the platform is made available to a customer. Access to the platform represents a series of distinct services as the Company continually provides access to, and fulfills its obligation to the end customer over the subscription term. The series of distinct services represents a single performance obligation that is satisfied over time. The Company recognizes revenue ratably because the customer receives and consumes the benefits of the platform throughout the contract period. The Company’s contracts are generally non-cancelable. The Company bills in advance for monthly contracts and typically bills annually in advance for contracts with terms of one year or longer . The Company also recognizes an immaterial amount of contract assets, or unbilled receivables, primarily relating to consideration for services completed but not billed at the reporting date. Unbilled receivables are classified as receivables when the Company has the right to invoice the customer. The Company records contract liabilities when cash payments are received or due in advance of performance to deferred revenue. Deferred revenue primarily relates to the advance consideration received from the customer. The price of subscriptions is generally fixed at contract inception and therefore, the Company’s contracts do not contain a significant amount of variable consideration. As a result, the amount of revenue recognized in the periods presented from performance obligations satisfied (or partially satisfied) in previous periods was not material. The Company recognized $257.5 million and $222.6 million of revenue during the three months ended March 31, 2020, and 2019, respectively, that was included in the deferred revenue balances at the beginning of their respective periods. As of March 31, 2020 , future estimated revenue related to performance obligations that were unsatisfied or partially unsatisfied was $630.0 million . The substantial majority of the unsatisfied performance obligations will be satisfied over the next twelve months . Stock-based compensation The Company has granted RSUs to its employees and members of the Board of Directors under the 2008 Equity Incentive Plan (“2008 Plan”), the 2017 Equity Incentive Plan (“2017 Plan”), and the 2018 Equity Incentive Plan ("2018 Plan" and together with the 2008 Plan and 2017 Plan, the "Dropbox Equity Incentive Plans"). The Company has granted the following types of RSUs under the Dropbox Equity Incentives Plans: • One-tier RSUs, which have a service-based vesting condition over a four -year period. These awards typically have a cliff vesting period of one year and continue to vest quarterly thereafter. The Company began granting one-tier RSUs under its 2008 Plan in August 2015, and it continues to grant one-tier RSUs under its 2018 Plan. The Company recognizes compensation expense associated with one-tier RSUs ratably on a straight-line basis over the requisite service period and accounts for forfeitures in the period in which they occur. • Two-tier RSUs, which had both a service-based vesting condition and a Performance Vesting Condition. The Performance Vesting Condition was satisfied on the effectiveness of the registration statement related to the Company's IPO. Prior to August 2015, the Company granted two-tier RSUs under the 2008 Plan. The last grant date for two-tier RSUs was in May 2015. The Company recognized compensation expense associated with two-tier RSUs using the accelerated attribution method over the requisite service period. As of March 31, 2020 , the Company only had one-tier RSUs outstanding under the Dropbox Equity Incentive Plans. Since August 2015, the Company has granted one-tier RSUs as the only stock-based payment awards to its employees, with the exception of awards granted to its co-founders and certain executives, and has not granted any stock options to employees since then. The fair values of the common stock underlying the RSUs granted in periods prior to the date of the Company's IPO were determined by the Board of Directors, with input from management and contemporaneous third-party valuations, which were performed at least quarterly. For valuations after the Company's IPO, the Board of Directors determines the fair value of each share of underlying common stock based on the closing price of the Company's Class A common stock as reported on the Nasdaq Global Select Market on the date of the grant. In connection with the acquisition of JN Projects, Inc. (d/b/a HelloSign) ("HelloSign"), the Company assumed unvested stock options that had been granted under the HelloSign's 2011 Equity Incentive Plan. The fair value of options assumed were based upon the Black-Scholes option-pricing model, see Note 12, "Stockholders' Equity" for further information. In December 2017, the Board of Directors approved a grant to the Company’s co-founders of restricted stock awards (“RSAs”) with respect to 14.7 million shares of Class A Common Stock in the aggregate (collectively, the “Co-Founder Grants”), of which 10.3 million RSAs were granted to Mr. Houston, the Company’s co-founder and Chief Executive Officer, and 4.4 million RSAs were granted to Mr. Ferdowsi, the Company’s co-founder and Director. These Co-Founder Grants have service-based, market-based, and performance-based vesting conditions. The Company estimated the grant date fair value of the Co-Founder Grants using a model based on multiple stock price paths developed through the use of a Monte Carlo simulation that incorporates into the valuation the possibility that the Stock Price Targets may not be satisfied. Effective March 19, 2020, Mr. Ferdowsi resigned as a member of the Board of Directors and as an officer of the Company. As of the date of Mr. Ferdowsi's resignation, none of the Stock Price Targets had been met, resulting in the forfeiture of his 4.4 million RSAs. See Note 12, "Stockholders' Equity" for further information. Cost of revenue Cost of revenue consists primarily of expenses associated with the storage, delivery, and distribution of the Company’s platform for both paying users and free users, also known as Basic users. These costs, which are referred to as infrastructure costs, include depreciation of servers located in co-location facilities that the Company leases and operates, rent and facilities expense for those datacenters, network and bandwidth costs, support and maintenance costs for infrastructure equipment, and payments to third-party datacenter service providers. Cost of revenue also includes costs, such as salaries, bonuses, benefits, travel-related expenses, and stock-based compensation, which are referred to as employee-related costs, for employees whose primary responsibilities relate to supporting the Company’s infrastructure and delivering user support. Other non-employee costs included in cost of revenue include credit card fees related to processing customer transactions and allocated overhead, such as facilities, including rent, utilities, depreciation on leasehold improvements and other equipment shared by all departments, and shared information technology costs. In addition, cost of revenue includes amortization of developed technologies, professional fees related to user support initiatives, and property taxes related to the datacenters. Cash and cash equivalents Cash consists primarily of cash on deposit with banks and includes amounts in transit from payment processors for credit and debit card transactions, which typically settle within five business days. Cash equivalents include highly liquid investments purchased with an original maturity date of 90 days or less from the date of purchase. The Company monitors its credit risk by considering factors such as historical experience, credit ratings, current economic conditions, and reasonable and supportable forecasts. Short-term investments The Company’s short-term investments are primarily comprised of corporate notes and obligations, U.S. Treasury securities, certificates of deposit, asset-backed securities, commercial paper, equity securities, U.S. agency obligations, supranational securities, and municipal securities. The Company determines the appropriate classification of its short-term investments at the time of purchase and reevaluates such designation at each balance sheet date. With the exception of the equity security, the Company has classified and accounted for its short-term investments as available-for-sale securities as the Company may sell these securities at any time for use in its current operations or for other purposes, even prior to maturity. As a result, the Company classifies its short-term investments, including securities with stated maturities beyond twelve months, within current assets in the condensed consolidated balance sheets. The Company's short-term investments are recorded at fair value each reporting period. Unrealized gains and losses on these short-term investments are reported as a separate component of accumulated other comprehensive income (loss) in the condensed consolidated balance sheets until realized. Unrealized gains and losses for any short-term investments that management intends to sell or it is more likely than not that management will be required to sell prior to their anticipated recovery are recorded in other income (expense), net. The Company segments its portfolio based on the underlying risk profiles of the securities and has a zero-loss expectation for U.S. treasury and U.S. government agency securities. The Company regularly reviews the securities in an unrealized loss position and evaluates the current expected credit loss by considering factors such as credit ratings, issuer-specific factors, current economic conditions, and reasonable and supportable forecasts. The Company did not record any credit losses for its short-term investments as of March 31, 2020 The Company holds an equity security in a publicly traded company in which the Company does not have a controlling interest or significant influence. The investment is measured using quoted prices in its active market with changes recorded in other income, net, in the condensed consolidated statement of operations. As of March 31, 2020, the Company's equity security totaled $20.6 million and is included in short-term investments in the condensed consolidated balance sheet. The Company recognized net gains of $11.0 million related to changes in quoted prices in the investment’s active market during the three months ended March 31, 2020. The investment is classified as a Level 1 investment within the fair value hierarchy. Concentrations of credit risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, accounts receivable, and short-term investments. The Company places its cash and cash equivalents, and short-term investments with well-established financial institutions. Trade accounts receivables are typically unsecured and are derived from revenue earned from customers located around the world. One distribution partner accounted for 53% of total trade and other receivables, net as of March 31, 2020 . Two distribution partners accounted for 10% and 27% of total trade and other receivables, net as of December 31, 2019 . No customer accounted for more than 10% of the Company’s revenue in the periods presented. Deferred commissions, net Deferred commissions, net is stated as gross deferred commissions less accumulated amortization. Sales commissions earned by the Company’s sales force and third-party resellers, as well as related payroll taxes, are considered to be incremental and recoverable costs of obtaining a contract with a customer. These amounts have been capitalized as deferred commissions within prepaid and other current assets and other assets on the condensed consolidated balance sheets. The Company deferred incremental costs of obtaining a contract of $7.8 million and $7.3 million during the three months ended March 31, 2020 and 2019, respectively. Deferred commissions, net included in prepaid and other current assets were $ 22.1 million and $19.9 million as of March 31, 2020 and December 31, 2019 , respectively. Deferred commissions, net included in other assets were $ 44.0 million and $43.5 million as of March 31, 2020 and December 31, 2019 , respectively. Deferred commissions are typically amortized over a period of benefit of five years . The period of benefit was estimated by considering factors such as historical customer attrition rates, the useful life of the Company’s technology, and the impact of competition in its industry. Amortized costs were $ 5.1 million and $ 3.9 million for the three months ended March 31, 2020 and 2019, respectively. Amortized costs are included in sales and marketing expense in the accompanying condensed consolidated statements of operations. There was no impairment loss in relation to the deferred costs for any period presented. Property and equipment, net Equipment is stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful life of the related asset, which is generally three to seven years . Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the term of the related lease. The following table presents the estimated useful lives of property and equipment: Property and equipment Useful life Buildings 20 to 30 years Datacenter and other computer equipment 3 to 5 years Office equipment and other 3 to 7 years Leasehold improvements Lesser of estimated useful life or remaining lease term Lease obligations The Company leases office space, datacenters, and equipment under non-cancelable finance and operating leases with various expiration dates through 2036. The Company determines if an arrangement contains a lease at inception. Operating lease right-of-use assets and lease liabilities are recognized at the present value of the future lease payments at commencement date. The interest rate implicit in the Company’s operating leases is not readily determinable, and therefore an incremental borrowing rate is estimated to determine the present value of future payments. The estimated incremental borrowing rate factors in a hypothetical interest rate on a collateralized basis with similar terms, payments, and economic environments. Operating lease right-of-use assets also include any prepaid lease payments and lease incentives. Certain of the operating lease agreements contain rent concession, rent escalation, and option to renew provisions. Rent concession and rent escalation provisions are considered in determining the single lease cost to be recorded over the lease term. Single lease cost is recognized on a straight-line basis over the lease term commencing on the date the Company has the right to use the leased property. The lease terms may include options to extend or terminate the lease. The Company generally uses the base, non-cancelable, lease term when recognizing the lease assets and liabilities, unless it is reasonably certain that the option will be exercised. In addition, certain of the Company’s operating lease agreements contain tenant improvement allowances from its landlords. These allowances are accounted for as lease incentives and decrease the Company's right-of-use asset and reduce single lease cost over the lease term. The Company leases certain equipment from various third parties, through equipment finance leases. These leases either include a bargain purchase option, a full transfer of ownership at the completion of the lease term, or the terms of the leases are at least 75 percent of the useful lives of the assets and are therefore classified as finance leases. These leases are capitalized in property and equipment, net and the related amortization of assets under finance leases is included in depreciation and amortization expense in the Company’s condensed consolidated statements of operations. Initial asset values and finance lease obligations are based on the present value of future minimum lease payments. The Company’s finance lease agreements may contain lease and non-lease components. The non-lease components include payments for support on infrastructure equipment obtained via finance leases, which when not significant in relation to the overall agreement, are combined with the lease components and accounted for together as a single lease component. Business combinations The Company uses best estimates and assumptions, including but not limited to, future expected cash flows, expected asset lives, and discount rates, to assign a fair value to the tangible and intangible assets acquired and liabilities assumed in business combinations as of the acquisition date. These estimates are inherently uncertain and subject to refinement. During the measurement period, which may be up to one year from the acquisition date, adjustments to the fair value of these tangible and intangible assets acquired and liabilities assumed may be recorded, with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the Company’s condensed consolidated statements of operations. Long-lived assets, including goodwill and other acquired intangible assets, net The Company evaluates the recoverability of its property and equipment and finite-lived intangible assets for possible impairment whenever events or circumstances indicate that the carrying amount of such assets may not be recoverable. The evaluation is performed at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. Recoverability of these assets is measured by a comparison of the carrying amounts to the future undiscounted cash flows the assets are expected to generate. If such review determines that the carrying amount of specific property and equipment or intangible assets is not recoverable, the carrying amount of such assets is reduced to its fair value. The Company reviews goodwill for impairment at least annually in the fourth quarter, or more frequently if events or changes in circumstances would more likely than not reduce the fair value of its single reporting unit below its carrying value. The Company has not recorded impairment charges on property and equipment, goodwill, or intangible assets for the periods presented in these condensed consolidated financial statements. Acquired property and equipment and finite-lived intangible assets are amortized over their useful lives. The Company evaluates the estimated remaining useful life of these assets when events or changes in circumstances warrant a revision to the remaining period of amortization. If the Company revises the estimated useful life assumption for any asset, the remaining unamortized balance is amortized or depreciated over the revised estimated useful life on a prospective basis. Income taxes Deferred income tax balances reflect the effects of temporary differences between the financial reporting and tax bases of the Company’s assets and liabilities using enacted tax rates expected to apply when taxes are actually paid or recovered. In addition, deferred tax assets are recorded for net operating loss and credit carryforwards. A valuation allowance is provided against deferred tax assets unless it is more likely than not that they will be realized based on all available positive and negative evidence. Such evidence includes, but is not limited to, recent cumulative earnings or losses, expectations of future taxable income by taxing jurisdiction, and the carry-forward periods available for the utilization of deferred tax assets. The Company uses a two-step approach to recognizing and measuring uncertain income tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained on audit. The second step is to measure the tax benefit as the largest amount which is more than 50% likely of being realized upon ultimate settlement. The Company recognizes interest and penalties related to unrecognized tax benefits as income tax expense. Although the Company believes that it has adequately reserved for its uncertain tax positions, it can provide no assurance that the final tax outcome of these matters will not be materially different. The Company evaluates its uncertain tax positions on a regular basis and evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, such as the 2017 Tax Cuts and Jobs Act ("2017 Tax Reform Act") and the 2020 Coronavirus Aid, Relief, and Economic Security Act ("2020 CARES Act"), correspondence with tax authorities during the course of an audit, and effective settlement of audit issues. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on the Company’s financial condition and results of operations. Fair value measurement The Company applies fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. The Company defines fair value as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining fair value measurements for assets and liabilities, the Company considers the principal or most advantageous market in which it would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as risks inherent in valuation techniques, transfer restrictions, and credit risk. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 —Inputs that are generally unobservable and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability. Recently adopted accounting pronouncements In June 2016, the 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 held at amortized cost. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. The Company adopted ASU No. 2016-13 on January 1, 2020 using the modified retrospective approach. The cumulative impact of transition to retained earnings, recorded as of the adoption date, was not material to the Company's consolidated financial statements. The Company did not record any material credit losses during the three months ended March 31, 2020. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820), which amends disclosure requirements for fair value measurements by requiring new disclosures, modifying existing requirements, and eliminating others. The amendments are the result of a broader disclosure project, which aims to improve the effectiveness of disclosures. The Company adopted ASU No. 2018-13 on January 1, 2020. The adoption of the standard did not have a material impact on the Company's consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40), Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The amendments in ASU No. 2018-15 amend the definition of a hosting arrangement and requires a customer in a hosting arrangement that is a service contract to capitalize certain costs as if the arrangement were an internal-use software project. The Company adopted ASU No. 2018-15 on January 1, 2020. The adoption of the standard did not have a material impact on the Company's consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes

Cash, Cash Equivalents and Shor

Cash, Cash Equivalents and Short-Term Investments	3 Months Ended
	Mar. 31, 2020
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Short-Term Investments	Note 2. Cash, Cash Equivalents and Short-Term Investments The amortized cost, unrealized gains and losses and estimated fair value of the Company's cash, cash equivalents and available-for-sale securities as of March 31, 2020 and December 31, 2019 consisted of the following: As of March 31, 2020 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Cash $ 112.1 $ — $ — $ 112.1 Cash equivalents Money market funds 373.0 — — 373.0 Commercial paper 1.3 — — 1.3 Total cash and cash equivalents $ 486.4 $ — $ — $ 486.4 Short-term investments Corporate notes and obligations 289.0 0.6 (2.7 ) 286.9 U.S. Treasury securities 173.3 2.1 — 175.4 Asset-backed securities 59.1 0.1 (0.7 ) 58.5 Certificates of deposit 30.8 — — 30.8 Commercial Paper 21.4 — — 21.4 U.S. agency obligations 15.3 0.2 — 15.5 Supranational securities 2.8 — — 2.8 Municipal securities 2.5 — — 2.5 Total available-for-sale securities 594.2 3.0 (3.4 ) 593.8 Total $ 1,080.6 $ 3.0 $ (3.4 ) $ 1,080.2 As of December 31, 2019 Amortized cost Unrealized gain Unrealized loss Estimated fair value Cash $ 105.0 $ — $ — $ 105.0 Cash equivalents: Money market funds 444.3 — — 444.3 Commercial paper 2.0 — — 2.0 Total cash and cash equivalents $ 551.3 $ — $ — $ 551.3 Investments — Corporate notes and obligations 285.5 1.2 (0.1 ) 286.6 U.S. Treasury securities 171.0 0.3 — $ 171.3 Asset backed securities 53.8 — — 53.8 Certificates of deposit 38.2 — — 38.2 U.S. agency obligations 27.2 — — $ 27.2 Commercial paper 24.2 — — 24.2 Supranational securities 4.0 — — 4.0 Municipal securities 2.4 — — 2.4 Total short-term investments 606.3 1.5 (0.1 ) 607.7 Total $ 1,157.6 $ 1.5 $ (0.1 ) $ 1,159.0 Included in cash and cash equivalents is cash in transit from payment processors for credit and debit card transactions of $11.8 million and $ 11.5 million as of March 31, 2020 and December 31, 2019 , respectively. With the exception of our equity security, all short-term investments were designated as available-for-sale securities as of March 31, 2020 . The total fair value of short-term investments was $614.4 million as of March 31, 2020. All short-term investments were designated as available-for-sale securities as of December 31, 2019 . The following table presents the contractual maturities of the Company’s available for sale securities as of March 31, 2020 : As of March 31, 2020 Amortized cost Estimated fair value Due within one year 288.3 289.1 Due between one to three years 280.8 280.1 Due after three years 25.1 24.6 Total $ 594.2 $ 593.8 The Company had 194 available-for-sale securities in unrealized loss positions as of March 31, 2020 . There were no material unrealized losses from available-for-sale securities and no material realized gains or losses from available-for-sale securities that were reclassified out of accumulated other comprehensive income (loss) for the three months ended March 31, 2020 and 2019. As of March 31, 2020, the Company’s short-term investments portfolio consisted of nine security types, two of which were in an unrealized loss position. The Company’s corporate notes and obligations and asset backed securities had unrealized losses of approximately $2.7 million and $0.7 million , respectively as of March 31, 2020. Unrealized losses on corporate notes and obligations and asset backed securities have not been recorded into income because management does not intend to sell nor will be required to sell these securities prior to their anticipated recovery, and for which the decline in fair value is largely due to changes in credit spreads. The credit ratings associated with the corporate notes and obligations and asset backed securities are mostly unchanged, are highly rated and the issuers continue to make timely principal and interest payments. The Company recorded $5.1 million and $ 6.2

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company measures its financial instruments at fair value each reporting period using a fair value hierarchy that prioritizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. A financial instrument’s classification within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The following table presents information about the Company’s financial instruments that are measured at fair value on a recurring basis using the input categories discussed in Note 1: As of March 31, 2020 Level 1 Level 2 Level 3 Total Cash equivalents Money market funds $ 373.0 $ — $ — $ 373.0 Commercial paper — 1.3 — 1.3 Total cash equivalents $ 373.0 $ 1.3 $ — $ 374.3 Short-term investments Corporate notes and obligations — 286.9 — 286.9 U.S. Treasury securities — 175.4 — 175.4 Asset backed securities — 58.5 — 58.5 Certificates of deposit — 30.8 — 30.8 Commercial paper — 21.4 — 21.4 Equity securities 20.6 — — 20.6 U.S agency obligations — 15.5 — 15.5 Supranational securities — 2.8 — 2.8 Municipal securities — 2.5 — 2.5 Total short-term investments $ 20.6 $ 593.8 $ — $ 614.4 Total cash equivalents and short-term investments $ 393.6 $ 595.1 $ — $ 988.7 As of December 31, 2019 Level 1 Level 2 Level 3 Total Cash equivalents Money market funds $ 444.3 $ — $ — $ 444.3 Commercial paper — 2.0 — 2.0 Total Cash Equivalents $ 444.3 $ 2.0 $ — $ 446.3 Short-term investments Corporate notes and obligations — 286.6 — 286.6 U.S. Treasury securities — 171.3 — 171.3 Asset-backed securities — 53.8 — 53.8 Certificates of deposit — 38.2 — 38.2 U.S. agency obligations — 27.2 — 27.2 Commercial paper — 24.2 — 24.2 Supranational securities — 4.0 — 4.0 Municipal securities — 2.4 — 2.4 Total short-term investments $ — $ 607.7 $ — $ 607.7 Equity Investments 9.8 — — 9.8 Total $ 454.1 $ 609.7 $ — $ 1,063.8 The Company had no transfers between levels of the fair value hierarchy. The carrying amounts of certain financial instruments, including cash held in banks, accounts receivable and accounts payable approximate fair value due to their short-term maturities and are excluded from the fair value table above.

Property and Equipment, Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2020
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net consisted of the following: As of March 31, 2020 December 31, 2019 Datacenter and other computer equipment 779.0 749.3 Furniture and fixtures 40.0 35.5 Leasehold improvements 231.4 211.4 Construction in progress 41.9 36.3 Total property and equipment 1,092.3 1,032.5 Accumulated depreciation and amortization (619.1 ) (587.2 ) Property and equipment, net $ 473.2 $ 445.3 The Company leases certain infrastructure from various third parties, through equipment finance leases. Infrastructure assets as of March 31, 2020 and December 31, 2019 , respectively included a total of $ 338.3 million and $321.8 million acquired under finance lease agreements. These leases are capitalized in property and equipment, and the related amortization of assets under finance leases is included in depreciation and amortization expense. The accumulated depreciation of the infrastructure under finance leases totaled $ 129.9 million and $124.6 million as of March 31, 2020 and December 31, 2019 , respectively. Construction in progress includes costs primarily related to construction of leasehold improvements for office buildings and datacenters. Depreciation expense related to property and equipment was $ 36.0 million and $ 43.1

Business Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Business Combinations	Business Combinations On February 8, 2019, the Company acquired all outstanding stock of JN Projects, Inc. (d/b/a HelloSign) ("HelloSign"), which provides an e-signature and document workflow platform. The acquisition of HelloSign expands the Company's content collaboration capabilities to include additional business-critical workflows. The results of HelloSign operations have been included in the Company’s consolidated results of operations since the date of acquisition. The purchase consideration transferred consisted of the following: Purchase consideration Cash paid to common and preferred stockholders and vested option holders $ 175.2 Transaction costs paid by Dropbox on behalf of HelloSign 2.4 Fair value of assumed HelloSign options attributable to pre-combination services (1) 0.8 Purchase price adjustments (0.5 ) Total purchase consideration $ 177.9 (1) The fair value of options assumed were based upon the Black-Scholes option-pricing model. In addition to the total purchase consideration above, the Company has employee holdback agreements with key HelloSign personnel consisting of $48.5 million in cash payments subject to on-going employee service. The related expenses are recognized within research and development expenses over the required service period of three years . The payments began in the current quarter, with $16.2 million paid during the three months ended March 31, 2020. The remaining balance of $32.3 million will be paid evenly in quarterly installments over the remaining required service period. The purchase consideration was allocated to the tangible and intangible assets and liabilities acquired as of the acquisition date, with the excess recorded to goodwill as shown below. Assets acquired: Cash and cash equivalents $ 5.5 Short-term investments 7.8 Acquisition-related intangible assets 44.6 Accounts receivable, prepaid and other assets 5.0 Total assets acquired $ 62.9 Liabilities assumed: Accounts payable, accrued and other liabilities $ 6.3 Deferred revenue 4.8 Deferred tax liability 6.9 Total liabilities assumed 18.0 Net assets acquired, excluding goodwill 44.9 Total purchase consideration 177.9 Goodwill (2) $ 133.0 (2) The goodwill recognized was primarily attributable to the opportunity to expand the user base of the Company's platform. The goodwill is not deductible for U.S. federal income tax purposes. The fair value of the separately identifiable finite-lived intangible assets acquired and estimated weighted average useful lives are as follows: Estimated fair values Estimated weighted average useful lives (In years) Customer relationships $ 20.5 4.9 Developed technology 19.6 5.0 Trade name 4.5 5.0 Total acquisition-related intangible assets $ 44.6 The fair values of the acquisition-related intangibles were determined using the following methodologies: the multi-period excess earnings method, replacement cost method, and the relief from royalty method, for customer relationships, developed technology, and the trade name, respectively. The valuation model inputs required the application of significant judgment by management. The acquired intangible assets have a total weighted average amortization period of 4.9 years. One-time acquisition-related diligence costs of $ 1.0

Intangible Assets

Intangible Assets	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Intangible assets consisted of the following: As of March 31, As of December 31, Weighted- (In years) 2020 2019 Developed technology $ 25.7 $ 25.8 3.8 Customer relationships 20.5 20.5 3.9 Software 20.5 20.0 1.4 Patents 13.0 13.0 7.5 Assembled workforce in asset acquisitions 12.6 12.6 0.8 Trademarks and trade names 5.2 5.2 3.9 Licenses 4.6 4.6 1.3 Other 3.3 3.3 5.4 Total intangibles 105.4 105.0 Accumulated amortization (61.0 ) (57.6 ) Intangible assets, net $ 44.4 $ 47.4 Amortization expense was $ 3.5 million and $ 2.8 million for the three months ended March 31, 2020 and 2019, respectively. Expected future amortization expense for intangible assets as of March 31, 2020 , is as follows: Remaining nine months of Fiscal 2020 $ 10.7 2021 11.7 2022 8.3 2023 7.7 2024 3.4 Thereafter 2.6 Total $ 44.4

Goodwill

Goodwill	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill Goodwill represents the excess of the purchase price in a business combination over the fair value of net tangible and intangible assets acquired. The changes in the carrying amounts of goodwill were as follows: Balance at December 31, 2019 $ 234.5 Effect of foreign currency translation (1.2 ) Balance at March 31, 2020 $ 233.3 Goodwill amounts are not amortized, but tested for impairment on an annual basis. There was no impairment of goodwill as of March 31, 2020 and December 31, 2019

Revolving Credit Facility

Revolving Credit Facility	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Revolving Credit Facility	Revolving Credit Facility In April 2017, the Company entered into an amended and restated credit and guaranty agreement which provided for a $600.0 million revolving loan facility (as amended from time to time, “revolving credit facility”). In conjunction with the revolving credit facility, the Company paid upfront issuance fees of $2.6 million , which are being amortized over the five -year term of the agreement. In February 2018, the Company amended the revolving credit facility to, among other things, permit the Company to make certain investments, enter into an unsecured standby letter of credit facility and increase its standby letter of credit sublimit to $187.5 million . The Company increased its borrowing capacity under the revolving credit facility from $600.0 million to $725.0 million . The Company may from time to time request increases in its borrowing capacity under the revolving credit facility of up to $275.0 million , provided no event of default has occurred or is continuing or would result from such increase. In conjunction with the amendment, the Company paid upfront issuance fees of $0.4 million , which are being amortized over the remaining term of the agreement. Pursuant to the terms of the revolving credit facility, the Company may issue letters of credit under the revolving credit facility, which reduce the total amount available for borrowing. Pursuant to the terms of the revolving credit facility, the Company is required to pay an annual commitment fee that accrues at a rate of 0.20% per annum on the unused portion of the borrowing commitments under the revolving credit facility. In addition, the Company is required to pay a fee in connection with letters of credit issued under the revolving credit facility, which accrues at a rate of 1.5% per annum on the amount of such letters of credit outstanding. There is an additional fronting fee of 0.125% per annum multiplied by the average aggregate daily maximum amount available under all letters of credit. Borrowings under the revolving credit facility bear interest, at the Company’s option, at an annual rate based on LIBOR plus a spread of 1.50% or at an alternative base rate plus a spread of 0.50% . The revolving credit facility contains customary conditions to borrowing, events of default and covenants, including covenants that restrict the Company’s ability to incur indebtedness, grant liens, make distributions to holders of the Company or its subsidiaries’ equity interests, make investments, or engage in transactions with its affiliates. In addition, the revolving credit facility contains financial covenants, including a consolidated leverage ratio covenant and a minimum liquidity balance of $100.0 million , which includes any available borrowing capacity. The Company was in compliance with the covenants of the revolving credit facility as of March 31, 2020 and December 31, 2019 , respectively. The Company had an aggregate of $45.6 million of letters of credit outstanding under the revolving credit facility as of March 31, 2020 , and the Company’s total available borrowing capacity under the revolving credit facility was $679.4 million as of March 31, 2020 . The Company’s letters of credit expire between April 2020 and September 2023 .

Leases

Leases	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Leases	Leases The Company has operating leases for corporate offices and datacenters, and finance leases for infrastructure equipment. The Company’s leases have remaining lease terms of 1 year to 16 years , some of which include options to extend the leases for up to 5 years . The Company also has subleases of former corporate offices. Subleases have remaining lease terms of 1 year to 4 years . Sublease income, which is recorded as a reduction of rental expense, was $ 1.8 million and $ 1.9 million for the three months ended March 31, 2020 and 2019, respectively. In 2017, the Company entered into a lease agreement for office space in San Francisco, California, to serve as its new corporate headquarters. The Company took initial possession of the first phase of its new corporate headquarters in June 2018, and began to recognize single lease cost related to the first phase. In that same period, the Company recorded a lease incentive obligation related to tenant improvement reimbursements associated with the first phase. In April 2019, the Company took possession of the second phase, and began to recognize additional lease costs and recorded an additional lease obligation, net of tenant improvement reimbursements related to the second phase. In December 2019, the Company took possession of the final phase, and began to recognize lease costs and lease obligation, net of tenant improvement reimbursements related to the third phase. The Company's total expected minimum obligations for all three phases of the lease are $ 831.2 million, which exclude expected tenant improvement reimbursements from the landlord of approximately $75.0 million and variable operating expenses. The Company’s obligations under the lease are supported by a $34.2 million letter of credit, which reduced the borrowing capacity under the revolving credit facility. In the three months ended March 31, 2020 , the Company collected tenant improvement reimbursements from the landlord totaling $ 8.5 million. Future minimum lease payments under non-cancellable leases as of March 31, 2020 were as follows: Year ending December 31, Operating leases (1) Finance leases 2020 (excluding the three months ended March 31, 2020) $ 91.3 $ 67.6 2021 114.5 78.1 2022 107.1 64 2023 91.1 30.4 2024 84.7 1.7 Thereafter 644.1 — Total future minimum lease payments 1,132.8 241.8 Less imputed interest (254.1 ) (13.9 ) Less tenant improvement receivables (22.9 ) — Total liability $ 855.8 $ 227.9 (1) Consists of future non-cancelable minimum rental payments under operating leases for the Company’s corporate offices and datacenters where the Company has possession, excluding rent payments from the Company’s sub-tenants and variable operating expenses. As of March 31, 2020 , the Company is entitled to non-cancelable rent payments from its sub-tenants of $31.9 million, which will be collected over the next 1 to 4 years. As of March 31, 2020 , the Company had commitments of $116.9 million for operating leases that have not yet commenced, and therefore are not included in the right-of-use asset or operating lease liability. These operating leases will commence between 2020 and 2021 with lease terms of 5 years to 15 years .
Leases	Leases The Company has operating leases for corporate offices and datacenters, and finance leases for infrastructure equipment. The Company’s leases have remaining lease terms of 1 year to 16 years , some of which include options to extend the leases for up to 5 years . The Company also has subleases of former corporate offices. Subleases have remaining lease terms of 1 year to 4 years . Sublease income, which is recorded as a reduction of rental expense, was $ 1.8 million and $ 1.9 million for the three months ended March 31, 2020 and 2019, respectively. In 2017, the Company entered into a lease agreement for office space in San Francisco, California, to serve as its new corporate headquarters. The Company took initial possession of the first phase of its new corporate headquarters in June 2018, and began to recognize single lease cost related to the first phase. In that same period, the Company recorded a lease incentive obligation related to tenant improvement reimbursements associated with the first phase. In April 2019, the Company took possession of the second phase, and began to recognize additional lease costs and recorded an additional lease obligation, net of tenant improvement reimbursements related to the second phase. In December 2019, the Company took possession of the final phase, and began to recognize lease costs and lease obligation, net of tenant improvement reimbursements related to the third phase. The Company's total expected minimum obligations for all three phases of the lease are $ 831.2 million, which exclude expected tenant improvement reimbursements from the landlord of approximately $75.0 million and variable operating expenses. The Company’s obligations under the lease are supported by a $34.2 million letter of credit, which reduced the borrowing capacity under the revolving credit facility. In the three months ended March 31, 2020 , the Company collected tenant improvement reimbursements from the landlord totaling $ 8.5 million. Future minimum lease payments under non-cancellable leases as of March 31, 2020 were as follows: Year ending December 31, Operating leases (1) Finance leases 2020 (excluding the three months ended March 31, 2020) $ 91.3 $ 67.6 2021 114.5 78.1 2022 107.1 64 2023 91.1 30.4 2024 84.7 1.7 Thereafter 644.1 — Total future minimum lease payments 1,132.8 241.8 Less imputed interest (254.1 ) (13.9 ) Less tenant improvement receivables (22.9 ) — Total liability $ 855.8 $ 227.9 (1) Consists of future non-cancelable minimum rental payments under operating leases for the Company’s corporate offices and datacenters where the Company has possession, excluding rent payments from the Company’s sub-tenants and variable operating expenses. As of March 31, 2020 , the Company is entitled to non-cancelable rent payments from its sub-tenants of $31.9 million, which will be collected over the next 1 to 4 years. As of March 31, 2020 , the Company had commitments of $116.9 million for operating leases that have not yet commenced, and therefore are not included in the right-of-use asset or operating lease liability. These operating leases will commence between 2020 and 2021 with lease terms of 5 years to 15 years .

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal matters From time to time, the Company is a party to a variety of claims, lawsuits, and proceedings which arise in the ordinary course of business, including claims of alleged infringement of intellectual property rights. The Company records a liability when it believes that it is probable that a loss will be incurred and the amount of loss or range of loss can be reasonably estimated. In its opinion, resolution of pending matters is not likely to have a material adverse impact on its condensed consolidated results of operations, cash flows, or its financial position. Given the unpredictable nature of legal proceedings, the Company bases its estimate on the information available at the time of the assessment. As additional information becomes available, the Company reassesses the potential liability and may revise the estimate. The Company is currently involved in four putative class action lawsuits alleging violations of the federal securities laws that were filed on August 30, 2019, September 5, 2019, September 13, 2019, and October 3, 2019, in the Superior Court of the State of California, San Mateo County, against the Company, certain of its officers and directors, underwriters of its IPO, and Sequoia Capital XII, L.P. and certain of its affiliated entities (collectively, the "Dropbox Defendants"). On October 4, 2019, two putative class action lawsuits alleging violations of the federal securities laws were filed against the Dropbox Defendants in the U.S. District Court for the Northern District of California (the "Federal Plaintiffs"). The six lawsuits each make the same or similar allegations of violations of federal securities laws, for allegedly making materially false and misleading statements in, or omitting material information from, the Company's IPO registration statement. The plaintiffs seek unspecified monetary damages and other relief. On March 2, 2020, the Federal Plaintiffs filed a consolidated class action complaint. The Company believes the cases are without merit and intends to vigorously defend them. The Company does not currently believe that this matter is likely to have a material adverse impact on its consolidated results of operations, cash flows, or financial position. Indemnification The Company’s arrangements generally include certain provisions for indemnifying customers against liabilities if its products or services infringe a third party’s intellectual property rights. It is not possible to determine the maximum potential amount under these indemnification obligations due to the limited history of prior indemnification claims. Other commitments

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	3 Months Ended
	Mar. 31, 2020
Payables and Accruals [Abstract]
Accrued and Other Current Liabilities	Accrued and Other Current Liabilities Accrued and other current liabilities consisted of the following: As of March 31, 2020 December 31, 2019 Non-income taxes payable 93.3 92.2 Accrued legal and other external fees 25.2 29.2 Other accrued and current liabilities 31.0 40.5 Total accrued and other current liabilities $ 149.5 $ 161.9

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Common stock The Company’s amended and restated certificate of incorporation authorizes the issuance of Class A common stock, Class B common stock, and Class C common stock. Holders of Class A common stock, Class B common stock, and Class C common stock are entitled to dividends on a pro rata basis, when, as, and if declared by the Company’s Board of Directors, subject to the rights of the holders of the Company’s preferred stock. Holders of Class A common stock are entitled to one vote per share, holders of Class B common stock are entitled to 10 votes per share, and holders of Class C common stock are entitled to zero votes per share. Holders of Class B common stock voluntarily converted 9.9 million and 11.8 million shares into an equivalent number shares of Class A common stock during the three months ended March 31, 2020 and 2019, respectively. As of March 31, 2020 , the Company had authorized 2,400.0 million shares of Class A common stock, 475.0 million shares of Class B common stock, and 800.0 million shares of Class C common stock, each at par value of $0.00001 . As of March 31, 2020 , 264.0 million shares of Class A common stock, 151.3 million shares of Class B common stock, and no shares of Class C common stock were issued and outstanding. As of December 31, 2019 , 255.8 million shares of Class A common stock, 161.2 million shares of Class B common stock, and no shares of Class C common stock were issued and outstanding. Class A shares issued and outstanding as of March 31, 2020 and December 31, 2019 exclude restricted stock awards granted to certain executives during the year and 10.3 million unvested restricted stock awards granted to one of the Company’s co-founders. See "Co-Founder Grants" section below for further details. Preferred stock The Company's Board of Directors will have the authority, without further action by the Company's stockholders, to issue up to 240.0 million shares of undesignated preferred stock with rights and preferences, including voting rights, designated from time to time by the Board of Directors. Stock repurchase program In February 2020, the Company's Board of Directors approved a stock repurchase program for the repurchase of up to $600 million of the Company’s outstanding shares of Class A common stock. Share repurchases will be subject to a review of the circumstances in place at that time and will be made from time to time in private transactions or open market purchases, as permitted by securities laws and other legal requirements. The program does not obligate the Company to repurchase any specific number of shares and may be discontinued at any time. During the three months ended March 31, 2020, the Company repurchased and subsequently retired 3.7 million shares of its Class A common stock for an aggregate amount of $64.0 million . Equity incentive plans Under the 2018 Plan, the Company may grant stock-based awards to purchase or directly issue shares of common stock to employees, directors, and consultants. Options are granted at a price per share equal to the fair market value of the Company's common stock at the date of grant. Options granted are exercisable over a maximum term of 10 years from the date of grant and generally vest over a period of four years . RSUs and RSAs are also granted under the 2018 Plan. The 2018 Plan will terminate 10 years after the later of (i) its adoption or (ii) the most recent stockholder-approved increase in the number of shares reserved under the 2018 Plan, unless terminated earlier by the Company's Board of Directors. The 2018 Plan was adopted on March 22, 2018. In connection with the acquisition of HelloSign, the Company assumed unvested stock options that had been granted under HelloSign's 2011 Equity Incentive Plan. As of March 31, 2020 , there were 30.4 million stock-based awards issued and outstanding and 88.3 million shares available for issuance under the Dropbox Equity Incentive Plans and HelloSign's 2011 Equity Incentive Plan (collectively, the "Plans"). Stock option and restricted stock activity for the Plans was as follows for the three months ended March 31, 2020 : Options outstanding Restricted stock outstanding Number of shares available for issuance under the Plans Number of shares outstanding under the Plans Weighted- average exercise price per share Weighted- average remaining contractual term (In years) Aggregate intrinsic value Number of shares outstanding under the Plans Weighted- average grant date fair value per share Balance at December 31, 2019 66.2 2.0 $ 12.28 6.5 $ 16.40 30.7 $ 20.48 Additional shares authorized 21.7 — — — — Options exercised and RSUs released — (0.1 ) 5.43 (2.7 ) 20.20 Options and RSUs canceled 3.3 (0.1 ) 23.38 (3.3 ) 20.51 Shares repurchased for tax withholdings on release of restricted stock 1.0 — — — 20.19 Restricted stock and options granted (3.9 ) 3.9 18.59 Balance at March 31, 2020 88.3 1.8 $ 12.36 6.3 $ 12.90 28.6 $ 20.25 Vested at March 31, 2020 1.2 $ 15.40 5.5 $ 6.40 — $ — Unvested at March 31, 2020 0.6 $ 5.26 $ 6.50 28.6 $ 20.25 The following table summarizes information about the pre-tax intrinsic value of options exercised during the three months ended March 31, 2020 and 2019 : Three months ended March 31, 2020 2019 Intrinsic value of options exercised $ 1.8 $ 3.1 As of March 31, 2020 , unamortized stock-based compensation related to unvested stock options, restricted stock awards (excluding the Co-Founder Grants), and RSUs was $600.1 million . The weighted-average period over which such compensation expense will be recognized if the requisite service is provided is approximately 2.5 years as of March 31, 2020 . The total fair value of released RSUs, as of their respective vesting dates, were $31.8 million and $67.9 million during the three months ended March 31, 2020 and March 31, 2019, respectively. Assumed stock options In connection with the acquisition of HelloSign the Company assumed 0.9 million unvested stock options which were valued using the Black-Scholes option-pricing model. The fair value of stock options assumed were estimated using the following assumptions: Expected volatility 51.6 % Expected term (in years) 3.4 - 7.0 Risk-free interest rate 2.42% - 2.51% Dividend yield — % Expected volatility. The expected volatility is based on the Company's historical volatility. Management believes this is the best estimate of the expected volatility over the expected life of its stock options. Expected term. The Company determines the expected term based on the average period the stock options are expected to remain outstanding, generally calculated as the midpoint of the stock options’ remaining vesting term and contractual expiration period, as the Company does not have sufficient historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior. Risk-free interest rate . The risk-free interest rate is based on the U.S. Treasury security in effect at the time the options were assumed for maturities corresponding with the expected term of the option. Expected dividend yield . The Company has not paid and does not expect to pay dividends. Consequently, the Company uses an expected dividend yield of zero . The estimated weighted-average grant date fair value for stock options assumed was $21.60 per share and total fair value of $ 19.4 million , of which, $18.6 million will be recognized as post-combination stock-based compensation expense. Co-Founder Grants In December 2017, the Board of Directors approved a grant to the Company’s co-founders of non-Plan RSAs with respect to 14.7 million shares of Class A Common Stock in the aggregate (collectively, the “Co-Founder Grants”), of which 10.3 million RSAs were granted to Mr. Houston, the Company’s co-founder and Chief Executive Officer, and 4.4 million RSAs were granted to Mr. Ferdowsi, the Company’s co-founder and Director. These Co-Founder Grants have service-based, market-based, and performance-based vesting conditions. The Co-Founder Grants are excluded from Class A common stock issued and outstanding until the satisfaction of these vesting conditions. The Co-Founder Grants also provide the holders with certain stockholder rights, such as the right to vote the shares with the other holders of Class A common stock and a right to cumulative declared dividends. However, the Co-Founder Grants are not considered a participating security for purposes of calculating net income (loss) per share attributable to common stockholders in Note 13, "Net Income (Loss) Per Share", as the right to the cumulative declared dividends is forfeitable if the service condition is not met. The Co-Founder Grants are eligible to vest over the ten -year period following the date the Company’s shares of Class A common stock commenced trading on the Nasdaq Global Select Market in connection with the Company’s IPO. The Co-Founder Grants comprise nine tranches that are eligible to vest based on the achievement of stock price goals, each of which are referred to as a Stock Price Target, measured over a consecutive thirty-day trading period during the Performance Period. The Performance Period began on January 1, 2019. During the first four years of the Performance Period, no more than 20% of the shares subject to each Co-Founder Grant would be eligible to vest in any calendar year. After the first four years , all shares are eligible to vest based on the achievement of the Stock Price Targets. The Company calculated the grant date fair value of the Co-Founder Grants based on multiple stock price paths developed through the use of a Monte Carlo simulation. A Monte Carlo simulation also calculates a derived service period for each of the nine vesting tranches, which is the measure of the expected time to achieve each Stock Price Target. A Monte Carlo simulation requires the use of various assumptions, including the underlying stock price, volatility, and the risk-free interest rate as of the valuation date, corresponding to the length of time remaining in the performance period, and expected dividend yield. The weighted-average grant date fair value of each Co-Founder Grant was estimated to be $10.60 per share. The weighted-average derived service period of each Co-Founder Grant was estimated to be 5.2 years, and ranged from 2.9 - 6.9 years. As of the valuation date, the Company expected to recognize an aggregate stock-based compensation expense of $156.2 million over the derived service period of each tranche using the accelerated attribution method as long as the co-founders satisfy their service-based vesting conditions. If the Stock Price Targets are met sooner than the derived service period, the Company will adjust its stock-based compensation to reflect the cumulative expense associated with the vested awards. The Company will recognize expense if the requisite service is provided, regardless of whether the market conditions are achieved. The Performance Vesting Condition for the Co-Founder Grants was satisfied on the date the Company’s shares of Class A common stock commenced trading on the Nasdaq Global Select Market in connection with the Company’s IPO, which was March 23, 2018. ​​In March 2020, one of the Company's co-founders, Mr. Ferdowsi, resigned as a member of the Board of Directors and as an officer of the Company. As of the date of Mr. Ferdowsi’s resignation, none of the Stock Price Targets had been met, resulting in the forfeiture of his 4.4 million RSAs. As he did not provide the requisite service associated with the Co-Founder Grants, the Company reversed all stock-based compensation expense that had been recognized from the grant date through March 19, 2020, which totaled $ 23.8 million, of which $21.5 million related to expense recognized prior to December 31, 2019, and ceased recognizing further expense related to the award. The Company recognized stock-based compensation expense related to the Co-Founder Grants of $6.1 million and $ 8.6 million during the three months ended March 31, 2020 and March 31, 2019, respectively. As of March 31, 2020 , unamortized stock-based compensation expense related to the Co-Founder Grants was $52.9 million .

Net Income (Loss) Per Share

Net Income (Loss) Per Share	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	Net Income (Loss) Per Share The Company computes net income (loss) per share using the two-class method required for multiple classes of common stock and participating securities. The rights, including the liquidation and dividend rights, of the Class A common stock and Class B common stock are substantially identical, other than voting rights. Accordingly, the Class A common stock and Class B common stock share equally in the Company’s net income and losses. Basic net income (loss) per share is computed by dividing net income attributable to common shareholders by the weighted-average number of shares of the Class A and Class B common stock outstanding. Diluted net income (loss) per share is computed by dividing net income attributable to common shareholders by the weighted-average number of diluted common shares outstanding. The computation of the diluted net income (loss) per share of Class A common stock assumes the conversion of our Class B common stock to Class A common stock, while the diluted net income (loss per share) of Class B common stock does not assume the conversion of those shares to Class A common stock. The numerators and denominators of the basic and diluted EPS computations for our common stock are calculated as follows (in millions, except for per share amounts): Three months ended March 31, Three months ended March 31, 2020 2019 Class A Class B Class A Class B Basic net income (loss) per share: Numerator Net income (loss) attributable to common stockholders $ 24.5 $ 14.8 $ (4.0 ) $ (3.7 ) Denominator Weighted-average number of common shares outstanding used in computing basic net income (loss) per share 260.0 157.3 215.1 195.4 Net income (loss) per common share, basic $ 0.09 $ 0.09 $ (0.02 ) $ (0.02 ) Diluted net income (loss) per share: Numerator Net income (loss) attributable to common shareholders $ 24.5 $ 14.8 $ (4.0 ) $ (3.7 ) Reallocation of net income as a result of conversion of Class B to Class A common stock $ 14.8 — — — Net income (loss) attributable to common stockholders for diluted EPS $ 39.3 $ 14.8 $ (4.0 ) $ (3.7 ) Denominator Weighted-average number of common shares outstanding used in computing diluted net income (loss) per share 260.0 157.3 215.1 195.4 Weighted-average effect of dilutive RSUs and employee stock options 1.6 0.4 — — Conversion of Class B to Class A common stock 157.3 — — — Weighted-average number of common shares outstanding used in computed diluted net income (loss) per share 418.9 157.7 215.1 195.4 Net income (loss) per common share, diluted $ 0.09 $ 0.09 $ (0.02 ) $ (0.02 ) The weighted-average impact of potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive was as follows: Three months ended 2020 2019 Restricted stock units 15.2 24.6 Restricted stock awards 0.2 — Options to purchase shares of common stock 1.3 1.8 Co-Founder Grants 14.2 14.7 Total 30.9 41.1

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company computed the year-to-date income tax provision by applying the estimated annual effective tax rate to the year-to-date pre-tax income and adjusted for discrete tax items in the period. The Company's income tax was an expense of $0.5 million for the three months ended March 31, 2020 , and a benefit of $5.7 million for the three months ended March 31, 2019 . The income tax expense for the three months ended March 31, 2020 was primarily attributable to foreign income tax and state income taxes. For the periods presented, the difference between the U.S. statutory rate and the Company's effective tax rate is primarily due to the full valuation allowance on its U.S. and Irish deferred tax assets. The effective tax rate is also impacted by earnings realized in foreign jurisdictions with statutory tax rates lower than the federal statutory tax rate. The Company periodically evaluates the realizability of its net deferred tax assets based on all available evidence, both positive and negative. The realization of net deferred tax assets is dependent on the Company's ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets. As of March 31, 2020 , the Company continues to maintain a full valuation allowance on its deferred tax assets in the U.S. and Ireland. However, the Company has partially benefited from its deferred tax assets due to the recognition of forecasted future income which is more likely than not to be earned in one of its foreign jurisdictions. The Company is subject to income tax audits in the U.S. and foreign jurisdictions. The Company records liabilities related to uncertain tax positions and believes that it has provided adequate reserves for income tax uncertainties in all open tax years. Unrecognized tax benefits increased by approximately $3.5 million for the three months ended March 31, 2020 , of which $0.4 million , if recognized, would affect the Company's effective tax rate. Additionally, unrecognized tax benefits decreased by approximately $0.2 million for the three months ended March 31, 2020 for statute of limitation lapses related to prior period tax positions.

Geographic Areas

Geographic Areas	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Geographic Areas	Geographic Areas Long-lived assets The following table sets forth long-lived assets by geographic area: As of March 31, 2020 December 31, 2019 United States $ 461.3 $ 431.9 International (1) 11.9 13.4 Total property and equipment, net $ 473.2 $ 445.3 (1) No single country other than the United States had a property and equipment balance greater than 10% of total property and equipment, net, as of March 31, 2020 and December 31, 2019 . Revenue Revenue by geography is generally based on the address of the customer as defined in the Company’s subscription agreement. The following table sets forth revenue by geographic area for the three months ended March 31, 2020 and 2019 . Three months ended March 31, 2020 2019 United States $ 235.6 $ 197.1 International (1) 219.4 188.5 Total revenue $ 455.0 $ 385.6 (1) No single country outside of the United States accounted for more than 10% of total revenue during the three months ended March 31, 2020 and 2019 .

Description of the Business a_2

Description of the Business and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of presentation	The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with the United States of America generally accepted accounting principles (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission ("SEC") regarding interim financial reporting. The accompanying unaudited condensed consolidated financial statements include the accounts of Dropbox and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Basis of consolidation	The condensed consolidated balance sheet as of December 31, 2019 included herein was derived from the audited financial statements as of that date. The unaudited condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the balance sheets, statements of operations, statements of comprehensive income (loss), statements of stockholders' equity and the statements of cash flows for the interim periods, but are not necessarily indicative of the results of operations to be anticipated for the full fiscal year ended December 31, 2020 or any future period.
Use of estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported and disclosed in the Company’s condensed consolidated financial statements and accompanying notes. These estimates are based on information available as of the date of the condensed consolidated financial statements. Management evaluates these estimates and assumptions on a regular basis. Actual results may differ materially from these estimates. The Company’s most significant estimates and judgments involves the valuation of acquired intangible assets and goodwill from business combinations.
Financial information about segments and geographic areas	The Company manages its operations and allocates resources as a single operating segment. Further, the Company manages, monitors, and reports its financials as a single reporting segment. The Company’s chief operating decision-maker is its Chief Executive Officer, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, assessing financial performance, and allocating resources.
Foreign currency transactions	The assets and liabilities of the Company’s foreign subsidiaries are translated from their respective functional currencies into U.S. dollars at the exchange rates in effect at the balance sheet date. Revenue and expense amounts are translated at the average exchange rate for the period. Foreign currency translation gains and losses are recorded in other comprehensive income (loss). Gains and losses realized from foreign currency transactions (those transactions denominated in currencies other than the foreign subsidiaries’ functional currency) are included in other income, net. Monetary assets and liabilities are remeasured using foreign currency exchange rates at the end of the period, and non-monetary assets are remeasured based on historical exchange
Revenue recognition and deferred commissions, net	Deferred commissions, net is stated as gross deferred commissions less accumulated amortization. Sales commissions earned by the Company’s sales force and third-party resellers, as well as related payroll taxes, are considered to be incremental and recoverable costs of obtaining a contract with a customer. These amounts have been capitalized as deferred commissions within prepaid and other current assets and other assets on the condensed consolidated balance sheets. The Company derives its revenue from subscription fees from customers for access to its platform. The Company’s policy is to exclude sales and other indirect taxes when measuring the transaction price of its subscription agreements. The Company accounts for revenue contracts with customers through the following steps: • Identification of the contract, or contracts, with a customer • Identification of the performance obligations in the contract • Determination of the transaction price • Allocation of the transaction price to the performance obligations in the contract • Recognition of revenue when, or as, the Company satisfies a performance obligation The Company’s subscription agreements generally have monthly or annual contractual terms and a small percentage have multi-year contractual terms. Revenue is recognized ratably over the related contractual term beginning on the date that the platform is made available to a customer. Access to the platform represents a series of distinct services as the Company continually provides access to, and fulfills its obligation to the end customer over the subscription term. The series of distinct services represents a single performance obligation that is satisfied over time. The Company recognizes revenue ratably because the customer receives and consumes the benefits of the platform throughout the contract period. The Company’s contracts are generally non-cancelable. The Company bills in advance for monthly contracts and typically bills annually in advance for contracts with terms of one year or longer . The Company also recognizes an immaterial amount of contract assets, or unbilled receivables, primarily relating to consideration for services completed but not billed at the reporting date. Unbilled receivables are classified as receivables when the Company has the right to invoice the customer. The Company records contract liabilities when cash payments are received or due in advance of performance to deferred revenue. Deferred revenue primarily relates to the advance consideration received from the customer. The price of subscriptions is generally fixed at contract inception and therefore, the Company’s contracts do not contain a significant amount of variable consideration. As a result, the amount of revenue recognized in the periods presented from performance obligations satisfied (or partially satisfied) in previous periods was not material.
Stock-based compensation	The Company has granted RSUs to its employees and members of the Board of Directors under the 2008 Equity Incentive Plan (“2008 Plan”), the 2017 Equity Incentive Plan (“2017 Plan”), and the 2018 Equity Incentive Plan ("2018 Plan" and together with the 2008 Plan and 2017 Plan, the "Dropbox Equity Incentive Plans"). The Company has granted the following types of RSUs under the Dropbox Equity Incentives Plans: • One-tier RSUs, which have a service-based vesting condition over a four -year period. These awards typically have a cliff vesting period of one year and continue to vest quarterly thereafter. The Company began granting one-tier RSUs under its 2008 Plan in August 2015, and it continues to grant one-tier RSUs under its 2018 Plan. The Company recognizes compensation expense associated with one-tier RSUs ratably on a straight-line basis over the requisite service period and accounts for forfeitures in the period in which they occur. • Two-tier RSUs, which had both a service-based vesting condition and a Performance Vesting Condition. The Performance Vesting Condition was satisfied on the effectiveness of the registration statement related to the Company's IPO. Prior to August 2015, the Company granted two-tier RSUs under the 2008 Plan. The last grant date for two-tier RSUs was in May 2015. The Company recognized compensation expense associated with two-tier RSUs using the accelerated attribution method over the requisite service period. As of March 31, 2020 , the Company only had one-tier RSUs outstanding under the Dropbox Equity Incentive Plans. Since August 2015, the Company has granted one-tier RSUs as the only stock-based payment awards to its employees, with the exception of awards granted to its co-founders and certain executives, and has not granted any stock options to employees since then. The fair values of the common stock underlying the RSUs granted in periods prior to the date of the Company's IPO were determined by the Board of Directors, with input from management and contemporaneous third-party valuations, which were performed at least quarterly. For valuations after the Company's IPO, the Board of Directors determines the fair value of each share of underlying common stock based on the closing price of the Company's Class A common stock as reported on the Nasdaq Global Select Market on the date of the grant. In connection with the acquisition of JN Projects, Inc. (d/b/a HelloSign) ("HelloSign"), the Company assumed unvested stock options that had been granted under the HelloSign's 2011 Equity Incentive Plan. The fair value of options assumed were based upon the Black-Scholes option-pricing model, see Note 12, "Stockholders' Equity" for further information. In December 2017, the Board of Directors approved a grant to the Company’s co-founders of restricted stock awards (“RSAs”) with respect to 14.7 million shares of Class A Common Stock in the aggregate (collectively, the “Co-Founder Grants”), of which 10.3 million RSAs were granted to Mr. Houston, the Company’s co-founder and Chief Executive Officer, and 4.4 million RSAs were granted to Mr. Ferdowsi, the Company’s co-founder and Director. These Co-Founder Grants have service-based, market-based, and performance-based vesting conditions. The Company estimated the grant date fair value of the Co-Founder Grants using a model based on multiple stock price paths developed through the use of a Monte Carlo simulation that incorporates into the valuation the possibility that the Stock Price Targets may not be satisfied. Effective March 19, 2020, Mr. Ferdowsi resigned as a member of the Board of Directors and as an officer of the Company. As of the date of Mr. Ferdowsi's resignation, none of the Stock Price Targets had been met, resulting in the forfeiture of his 4.4 million RSAs. See Note 12, "Stockholders' Equity" for further information.
Cost of revenue	Cost of revenue consists primarily of expenses associated with the storage, delivery, and distribution of the Company’s platform for both paying users and free users, also known as Basic users. These costs, which are referred to as infrastructure costs, include depreciation of servers located in co-location facilities that the Company leases and operates, rent and facilities expense for those datacenters, network and bandwidth costs, support and maintenance costs for infrastructure equipment, and payments to third-party datacenter service providers. Cost of revenue also includes costs, such as salaries, bonuses, benefits, travel-related expenses, and stock-based compensation, which are referred to as employee-related costs, for employees whose primary responsibilities relate to supporting the Company’s infrastructure and delivering user support. Other non-employee costs included in cost of revenue include credit card fees related to processing customer transactions and allocated overhead, such as facilities, including rent, utilities, depreciation on leasehold improvements and other equipment shared by all departments, and shared information technology costs. In addition, cost of revenue includes amortization of developed technologies, professional fees related to user support initiatives, and property taxes related to the datacenters.
Cash and cash equivalents	Cash consists primarily of cash on deposit with banks and includes amounts in transit from payment processors for credit and debit card transactions, which typically settle within five
Short-term investments	The Company’s short-term investments are primarily comprised of corporate notes and obligations, U.S. Treasury securities, certificates of deposit, asset-backed securities, commercial paper, equity securities, U.S. agency obligations, supranational securities, and municipal securities. The Company determines the appropriate classification of its short-term investments at the time of purchase and reevaluates such designation at each balance sheet date. With the exception of the equity security, the Company has classified and accounted for its short-term investments as available-for-sale securities as the Company may sell these securities at any time for use in its current operations or for other purposes, even prior to maturity. As a result, the Company classifies its short-term investments, including securities with stated maturities beyond twelve months, within current assets in the condensed consolidated balance sheets.
Concentrations of credit risk	Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, accounts receivable, and short-term investments. The Company places its cash and cash equivalents, and short-term investments with well-established financial institutions.
Property and equipment, net	Equipment is stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful life of the related asset, which is generally three to seven years . Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the term of the related lease. The following table presents the estimated useful lives of property and equipment: Property and equipment Useful life Buildings 20 to 30 years Datacenter and other computer equipment 3 to 5 years Office equipment and other 3 to 7 years Leasehold improvements Lesser of estimated useful life or remaining lease term
Lease obligations	The Company leases office space, datacenters, and equipment under non-cancelable finance and operating leases with various expiration dates through 2036. The Company determines if an arrangement contains a lease at inception. Operating lease right-of-use assets and lease liabilities are recognized at the present value of the future lease payments at commencement date. The interest rate implicit in the Company’s operating leases is not readily determinable, and therefore an incremental borrowing rate is estimated to determine the present value of future payments. The estimated incremental borrowing rate factors in a hypothetical interest rate on a collateralized basis with similar terms, payments, and economic environments. Operating lease right-of-use assets also include any prepaid lease payments and lease incentives. Certain of the operating lease agreements contain rent concession, rent escalation, and option to renew provisions. Rent concession and rent escalation provisions are considered in determining the single lease cost to be recorded over the lease term. Single lease cost is recognized on a straight-line basis over the lease term commencing on the date the Company has the right to use the leased property. The lease terms may include options to extend or terminate the lease. The Company generally uses the base, non-cancelable, lease term when recognizing the lease assets and liabilities, unless it is reasonably certain that the option will be exercised. In addition, certain of the Company’s operating lease agreements contain tenant improvement allowances from its landlords. These allowances are accounted for as lease incentives and decrease the Company's right-of-use asset and reduce single lease cost over the lease term. The Company leases certain equipment from various third parties, through equipment finance leases. These leases either include a bargain purchase option, a full transfer of ownership at the completion of the lease term, or the terms of the leases are at least 75 percent of the useful lives of the assets and are therefore classified as finance leases. These leases are capitalized in property and equipment, net and the related amortization of assets under finance leases is included in depreciation and amortization expense in the Company’s condensed consolidated statements of operations. Initial asset values and finance lease obligations are based on the present value of future minimum lease payments. The Company’s finance lease agreements may contain lease and non-lease components. The non-lease components include payments for support on infrastructure equipment obtained via finance leases, which when not significant in relation to the overall agreement, are combined with the lease components and accounted for together as a single lease component.
Business combinations	The Company uses best estimates and assumptions, including but not limited to, future expected cash flows, expected asset lives, and discount rates, to assign a fair value to the tangible and intangible assets acquired and liabilities assumed in business combinations as of the acquisition date. These estimates are inherently uncertain and subject to refinement. During the measurement period, which may be up to one year from the acquisition date, adjustments to the fair value of these tangible and intangible assets acquired and liabilities assumed may be recorded, with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the Company’s condensed consolidated statements of operations.
Long-lived assets, including goodwill and other acquired intangible assets, net	The Company evaluates the recoverability of its property and equipment and finite-lived intangible assets for possible impairment whenever events or circumstances indicate that the carrying amount of such assets may not be recoverable. The evaluation is performed at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. Recoverability of these assets is measured by a comparison of the carrying amounts to the future undiscounted cash flows the assets are expected to generate. If such review determines that the carrying amount of specific property and equipment or intangible assets is not recoverable, the carrying amount of such assets is reduced to its fair value. The Company reviews goodwill for impairment at least annually in the fourth quarter, or more frequently if events or changes in circumstances would more likely than not reduce the fair value of its single reporting unit below its carrying value. The Company has not recorded impairment charges on property and equipment, goodwill, or intangible assets for the periods presented in these condensed consolidated financial statements. Acquired property and equipment and finite-lived intangible assets are amortized over their useful lives. The Company evaluates the estimated remaining useful life of these assets when events or changes in circumstances warrant a revision to the remaining period of amortization. If the Company revises the estimated useful life assumption for any asset, the remaining unamortized balance is amortized or depreciated over the revised estimated useful life on a prospective basis.
Income taxes	Deferred income tax balances reflect the effects of temporary differences between the financial reporting and tax bases of the Company’s assets and liabilities using enacted tax rates expected to apply when taxes are actually paid or recovered. In addition, deferred tax assets are recorded for net operating loss and credit carryforwards. A valuation allowance is provided against deferred tax assets unless it is more likely than not that they will be realized based on all available positive and negative evidence. Such evidence includes, but is not limited to, recent cumulative earnings or losses, expectations of future taxable income by taxing jurisdiction, and the carry-forward periods available for the utilization of deferred tax assets. The Company uses a two-step approach to recognizing and measuring uncertain income tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained on audit. The second step is to measure the tax benefit as the largest amount which is more than 50% likely of being realized upon ultimate settlement. The Company recognizes interest and penalties related to unrecognized tax benefits as income tax expense. Although the Company believes that it has adequately reserved for its uncertain tax positions, it can provide no assurance that the final tax outcome of these matters will not be materially different. The Company evaluates its uncertain tax positions on a regular basis and evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, such as the 2017 Tax Cuts and Jobs Act ("2017 Tax Reform Act") and the 2020 Coronavirus Aid, Relief, and Economic Security Act ("2020 CARES Act"), correspondence with tax authorities during the course of an audit, and effective settlement of audit issues. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on the Company’s financial condition and results of operations.
Fair value measurement	The Company applies fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. The Company defines fair value as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining fair value measurements for assets and liabilities, the Company considers the principal or most advantageous market in which it would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as risks inherent in valuation techniques, transfer restrictions, and credit risk. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 —Inputs that are generally unobservable and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability.
Recently issued accounting pronouncements not yet adopted and Recently adopted accounting pronouncements	In June 2016, the 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 held at amortized cost. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. The Company adopted ASU No. 2016-13 on January 1, 2020 using the modified retrospective approach. The cumulative impact of transition to retained earnings, recorded as of the adoption date, was not material to the Company's consolidated financial statements. The Company did not record any material credit losses during the three months ended March 31, 2020. In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820), which amends disclosure requirements for fair value measurements by requiring new disclosures, modifying existing requirements, and eliminating others. The amendments are the result of a broader disclosure project, which aims to improve the effectiveness of disclosures. The Company adopted ASU No. 2018-13 on January 1, 2020. The adoption of the standard did not have a material impact on the Company's consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40), Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The amendments in ASU No. 2018-15 amend the definition of a hosting arrangement and requires a customer in a hosting arrangement that is a service contract to capitalize certain costs as if the arrangement were an internal-use software project. The Company adopted ASU No. 2018-15 on January 1, 2020. The adoption of the standard did not have a material impact on the Company's consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes
Goodwill
Net loss per share	The Company computes net income (loss) per share using the two-class method required for multiple classes of common stock and participating securities. The rights, including the liquidation and dividend rights, of the Class A common stock and Class B common stock are substantially identical, other than voting rights. Accordingly, the Class A common stock and Class B common stock share equally in the Company’s net income and losses. Basic net income (loss) per share is computed by dividing net income attributable to common shareholders by the weighted-average number of shares of the Class A and Class B common stock outstanding. Diluted net income (loss) per share is computed by dividing net income attributable to common shareholders by the weighted-average number of diluted common shares outstanding. The computation of the diluted net income (loss) per share of Class A common stock assumes the conversion of our Class B common stock to Class A common stock, while the diluted net income (loss per share) of Class B common stock does not assume the conversion of those shares to Class A common stock.

Description of the Business a_3

Description of the Business and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of estimated useful lives of property and equipment	The following table presents the estimated useful lives of property and equipment: Property and equipment Useful life Buildings 20 to 30 years Datacenter and other computer equipment 3 to 5 years Office equipment and other 3 to 7 years Leasehold improvements Lesser of estimated useful life or remaining lease term Property and equipment, net consisted of the following: As of March 31, 2020 December 31, 2019 Datacenter and other computer equipment 779.0 749.3 Furniture and fixtures 40.0 35.5 Leasehold improvements 231.4 211.4 Construction in progress 41.9 36.3 Total property and equipment 1,092.3 1,032.5 Accumulated depreciation and amortization (619.1 ) (587.2 ) Property and equipment, net $ 473.2 $ 445.3

Cash, Cash Equivalents and Sh_2

Cash, Cash Equivalents and Short-Term Investments (Tables)	3 Months Ended
	Mar. 31, 2020
Cash and Cash Equivalents [Abstract]
Schedule of cash, cash equivalents and short-term investments	The amortized cost, unrealized gains and losses and estimated fair value of the Company's cash, cash equivalents and available-for-sale securities as of March 31, 2020 and December 31, 2019 consisted of the following: As of March 31, 2020 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Cash $ 112.1 $ — $ — $ 112.1 Cash equivalents Money market funds 373.0 — — 373.0 Commercial paper 1.3 — — 1.3 Total cash and cash equivalents $ 486.4 $ — $ — $ 486.4 Short-term investments Corporate notes and obligations 289.0 0.6 (2.7 ) 286.9 U.S. Treasury securities 173.3 2.1 — 175.4 Asset-backed securities 59.1 0.1 (0.7 ) 58.5 Certificates of deposit 30.8 — — 30.8 Commercial Paper 21.4 — — 21.4 U.S. agency obligations 15.3 0.2 — 15.5 Supranational securities 2.8 — — 2.8 Municipal securities 2.5 — — 2.5 Total available-for-sale securities 594.2 3.0 (3.4 ) 593.8 Total $ 1,080.6 $ 3.0 $ (3.4 ) $ 1,080.2 As of December 31, 2019 Amortized cost Unrealized gain Unrealized loss Estimated fair value Cash $ 105.0 $ — $ — $ 105.0 Cash equivalents: Money market funds 444.3 — — 444.3 Commercial paper 2.0 — — 2.0 Total cash and cash equivalents $ 551.3 $ — $ — $ 551.3 Investments — Corporate notes and obligations 285.5 1.2 (0.1 ) 286.6 U.S. Treasury securities 171.0 0.3 — $ 171.3 Asset backed securities 53.8 — — 53.8 Certificates of deposit 38.2 — — 38.2 U.S. agency obligations 27.2 — — $ 27.2 Commercial paper 24.2 — — 24.2 Supranational securities 4.0 — — 4.0 Municipal securities 2.4 — — 2.4 Total short-term investments 606.3 1.5 (0.1 ) 607.7 Total $ 1,157.6 $ 1.5 $ (0.1 ) $ 1,159.0
Contractual maturities of short term investments	The following table presents the contractual maturities of the Company’s available for sale securities as of March 31, 2020 : As of March 31, 2020 Amortized cost Estimated fair value Due within one year 288.3 289.1 Due between one to three years 280.8 280.1 Due after three years 25.1 24.6 Total $ 594.2 $ 593.8

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of fair value assets measured on recurring basis	The following table presents information about the Company’s financial instruments that are measured at fair value on a recurring basis using the input categories discussed in Note 1: As of March 31, 2020 Level 1 Level 2 Level 3 Total Cash equivalents Money market funds $ 373.0 $ — $ — $ 373.0 Commercial paper — 1.3 — 1.3 Total cash equivalents $ 373.0 $ 1.3 $ — $ 374.3 Short-term investments Corporate notes and obligations — 286.9 — 286.9 U.S. Treasury securities — 175.4 — 175.4 Asset backed securities — 58.5 — 58.5 Certificates of deposit — 30.8 — 30.8 Commercial paper — 21.4 — 21.4 Equity securities 20.6 — — 20.6 U.S agency obligations — 15.5 — 15.5 Supranational securities — 2.8 — 2.8 Municipal securities — 2.5 — 2.5 Total short-term investments $ 20.6 $ 593.8 $ — $ 614.4 Total cash equivalents and short-term investments $ 393.6 $ 595.1 $ — $ 988.7 As of December 31, 2019 Level 1 Level 2 Level 3 Total Cash equivalents Money market funds $ 444.3 $ — $ — $ 444.3 Commercial paper — 2.0 — 2.0 Total Cash Equivalents $ 444.3 $ 2.0 $ — $ 446.3 Short-term investments Corporate notes and obligations — 286.6 — 286.6 U.S. Treasury securities — 171.3 — 171.3 Asset-backed securities — 53.8 — 53.8 Certificates of deposit — 38.2 — 38.2 U.S. agency obligations — 27.2 — 27.2 Commercial paper — 24.2 — 24.2 Supranational securities — 4.0 — 4.0 Municipal securities — 2.4 — 2.4 Total short-term investments $ — $ 607.7 $ — $ 607.7 Equity Investments 9.8 — — 9.8 Total $ 454.1 $ 609.7 $ — $ 1,063.8

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2020
Property, Plant and Equipment [Abstract]
Schedule of property and equipment, net	The following table presents the estimated useful lives of property and equipment: Property and equipment Useful life Buildings 20 to 30 years Datacenter and other computer equipment 3 to 5 years Office equipment and other 3 to 7 years Leasehold improvements Lesser of estimated useful life or remaining lease term Property and equipment, net consisted of the following: As of March 31, 2020 December 31, 2019 Datacenter and other computer equipment 779.0 749.3 Furniture and fixtures 40.0 35.5 Leasehold improvements 231.4 211.4 Construction in progress 41.9 36.3 Total property and equipment 1,092.3 1,032.5 Accumulated depreciation and amortization (619.1 ) (587.2 ) Property and equipment, net $ 473.2 $ 445.3

Business Combinations (Tables)

Business Combinations (Tables)	3 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Schedule of purchase consideration transferred	The purchase consideration transferred consisted of the following: Purchase consideration Cash paid to common and preferred stockholders and vested option holders $ 175.2 Transaction costs paid by Dropbox on behalf of HelloSign 2.4 Fair value of assumed HelloSign options attributable to pre-combination services (1) 0.8 Purchase price adjustments (0.5 ) Total purchase consideration $ 177.9 (1) The fair value of options assumed were based upon the Black-Scholes option-pricing model.
Schedule of recognized identified assets acquired and liabilities assumed	Assets acquired: Cash and cash equivalents $ 5.5 Short-term investments 7.8 Acquisition-related intangible assets 44.6 Accounts receivable, prepaid and other assets 5.0 Total assets acquired $ 62.9 Liabilities assumed: Accounts payable, accrued and other liabilities $ 6.3 Deferred revenue 4.8 Deferred tax liability 6.9 Total liabilities assumed 18.0 Net assets acquired, excluding goodwill 44.9 Total purchase consideration 177.9 Goodwill (2) $ 133.0 (2) The goodwill recognized was primarily attributable to the opportunity to expand the user base of the Company's platform. The goodwill is not deductible for U.S. federal income tax purposes.
Schedule of finite-lived intangible assets acquired and estimated useful lives	The fair value of the separately identifiable finite-lived intangible assets acquired and estimated weighted average useful lives are as follows: Estimated fair values Estimated weighted average useful lives (In years) Customer relationships $ 20.5 4.9 Developed technology 19.6 5.0 Trade name 4.5 5.0 Total acquisition-related intangible assets $ 44.6

Intangible Assets (Tables)

Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of intangible assets	Intangible assets consisted of the following: As of March 31, As of December 31, Weighted- (In years) 2020 2019 Developed technology $ 25.7 $ 25.8 3.8 Customer relationships 20.5 20.5 3.9 Software 20.5 20.0 1.4 Patents 13.0 13.0 7.5 Assembled workforce in asset acquisitions 12.6 12.6 0.8 Trademarks and trade names 5.2 5.2 3.9 Licenses 4.6 4.6 1.3 Other 3.3 3.3 5.4 Total intangibles 105.4 105.0 Accumulated amortization (61.0 ) (57.6 ) Intangible assets, net $ 44.4 $ 47.4
Schedule of future amortization expense	Expected future amortization expense for intangible assets as of March 31, 2020 , is as follows: Remaining nine months of Fiscal 2020 $ 10.7 2021 11.7 2022 8.3 2023 7.7 2024 3.4 Thereafter 2.6 Total $ 44.4

Goodwill (Tables)

Goodwill (Tables)	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill	The changes in the carrying amounts of goodwill were as follows: Balance at December 31, 2019 $ 234.5 Effect of foreign currency translation (1.2 ) Balance at March 31, 2020 $ 233.3

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Maturities of operating lease liabilities	million. Future minimum lease payments under non-cancellable leases as of March 31, 2020 were as follows: Year ending December 31, Operating leases (1) Finance leases 2020 (excluding the three months ended March 31, 2020) $ 91.3 $ 67.6 2021 114.5 78.1 2022 107.1 64 2023 91.1 30.4 2024 84.7 1.7 Thereafter 644.1 — Total future minimum lease payments 1,132.8 241.8 Less imputed interest (254.1 ) (13.9 ) Less tenant improvement receivables (22.9 ) — Total liability $ 855.8 $ 227.9 (1) Consists of future non-cancelable minimum rental payments under operating leases for the Company’s corporate offices and datacenters where the Company has possession, excluding rent payments from the Company’s sub-tenants and variable operating expenses. As of March 31, 2020 , the Company is entitled to non-cancelable rent payments from its sub-tenants of $31.9 million, which will be collected over the next 1 to 4 years.
Maturities of finance lease liabilities	million. Future minimum lease payments under non-cancellable leases as of March 31, 2020 were as follows: Year ending December 31, Operating leases (1) Finance leases 2020 (excluding the three months ended March 31, 2020) $ 91.3 $ 67.6 2021 114.5 78.1 2022 107.1 64 2023 91.1 30.4 2024 84.7 1.7 Thereafter 644.1 — Total future minimum lease payments 1,132.8 241.8 Less imputed interest (254.1 ) (13.9 ) Less tenant improvement receivables (22.9 ) — Total liability $ 855.8 $ 227.9 (1) Consists of future non-cancelable minimum rental payments under operating leases for the Company’s corporate offices and datacenters where the Company has possession, excluding rent payments from the Company’s sub-tenants and variable operating expenses. As of March 31, 2020 , the Company is entitled to non-cancelable rent payments from its sub-tenants of $31.9 million, which will be collected over the next 1 to 4 years.

Accrued and Other Current Lia_2

Accrued and Other Current Liabilities (Tables)	3 Months Ended
	Mar. 31, 2020
Payables and Accruals [Abstract]
Schedule of accrued and other current liabilities	Accrued and other current liabilities consisted of the following: As of March 31, 2020 December 31, 2019 Non-income taxes payable 93.3 92.2 Accrued legal and other external fees 25.2 29.2 Other accrued and current liabilities 31.0 40.5 Total accrued and other current liabilities $ 149.5 $ 161.9

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Schedule of stock option and restricted stock activity	Stock option and restricted stock activity for the Plans was as follows for the three months ended March 31, 2020 : Options outstanding Restricted stock outstanding Number of shares available for issuance under the Plans Number of shares outstanding under the Plans Weighted- average exercise price per share Weighted- average remaining contractual term (In years) Aggregate intrinsic value Number of shares outstanding under the Plans Weighted- average grant date fair value per share Balance at December 31, 2019 66.2 2.0 $ 12.28 6.5 $ 16.40 30.7 $ 20.48 Additional shares authorized 21.7 — — — — Options exercised and RSUs released — (0.1 ) 5.43 (2.7 ) 20.20 Options and RSUs canceled 3.3 (0.1 ) 23.38 (3.3 ) 20.51 Shares repurchased for tax withholdings on release of restricted stock 1.0 — — — 20.19 Restricted stock and options granted (3.9 ) 3.9 18.59 Balance at March 31, 2020 88.3 1.8 $ 12.36 6.3 $ 12.90 28.6 $ 20.25 Vested at March 31, 2020 1.2 $ 15.40 5.5 $ 6.40 — $ — Unvested at March 31, 2020 0.6 $ 5.26 $ 6.50 28.6 $ 20.25
Schedule of pre-tax intrinsic value	The following table summarizes information about the pre-tax intrinsic value of options exercised during the three months ended March 31, 2020 and 2019 : Three months ended March 31, 2020 2019 Intrinsic value of options exercised $ 1.8 $ 3.1
Fair value of stock options assumptions used	The fair value of stock options assumed were estimated using the following assumptions: Expected volatility 51.6 % Expected term (in years) 3.4 - 7.0 Risk-free interest rate 2.42% - 2.51% Dividend yield — %

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	Three months ended March 31, Three months ended March 31, 2020 2019 Class A Class B Class A Class B Basic net income (loss) per share: Numerator Net income (loss) attributable to common stockholders $ 24.5 $ 14.8 $ (4.0 ) $ (3.7 ) Denominator Weighted-average number of common shares outstanding used in computing basic net income (loss) per share 260.0 157.3 215.1 195.4 Net income (loss) per common share, basic $ 0.09 $ 0.09 $ (0.02 ) $ (0.02 ) Diluted net income (loss) per share: Numerator Net income (loss) attributable to common shareholders $ 24.5 $ 14.8 $ (4.0 ) $ (3.7 ) Reallocation of net income as a result of conversion of Class B to Class A common stock $ 14.8 — — — Net income (loss) attributable to common stockholders for diluted EPS $ 39.3 $ 14.8 $ (4.0 ) $ (3.7 ) Denominator Weighted-average number of common shares outstanding used in computing diluted net income (loss) per share 260.0 157.3 215.1 195.4 Weighted-average effect of dilutive RSUs and employee stock options 1.6 0.4 — — Conversion of Class B to Class A common stock 157.3 — — — Weighted-average number of common shares outstanding used in computed diluted net income (loss) per share 418.9 157.7 215.1 195.4 Net income (loss) per common share, diluted $ 0.09 $ 0.09 $ (0.02 ) $ (0.02 )
Schedule of potentially dilutive securities excluded from computation of earnings per share	The weighted-average impact of potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive was as follows: Three months ended 2020 2019 Restricted stock units 15.2 24.6 Restricted stock awards 0.2 — Options to purchase shares of common stock 1.3 1.8 Co-Founder Grants 14.2 14.7 Total 30.9 41.1

Geographic Areas (Tables)

Geographic Areas (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Long-lived assets by geographic areas	The following table sets forth long-lived assets by geographic area: As of March 31, 2020 December 31, 2019 United States $ 461.3 $ 431.9 International (1) 11.9 13.4 Total property and equipment, net $ 473.2 $ 445.3 (1) No single country other than the United States had a property and equipment balance greater than 10% of total property and equipment, net, as of March 31, 2020 and December 31, 2019
Revenue by geographic areas	The following table sets forth revenue by geographic area for the three months ended March 31, 2020 and 2019 . Three months ended March 31, 2020 2019 United States $ 235.6 $ 197.1 International (1) 219.4 188.5 Total revenue $ 455.0 $ 385.6 (1) No single country outside of the United States accounted for more than 10% of total revenue during the three months ended March 31, 2020 and 2019

Description of the Business a_4

Description of the Business and Summary of Significant Accounting Policies - Foreign Currency Transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Foreign currency transaction losses	$ 1.2	$ 0.1

Description of the Business a_5

Description of the Business and Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Revenue, performance obligation, description of timing	one year or longer
Revenue recognized	$ 257.5	$ 222.6
Remaining performance obligation	$ 630
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligation satisfaction period	12 months

Description of the Business a_6

Description of the Business and Summary of Significant Accounting Policies - Stock-based Compensation (Details) - shares shares in Millions	Mar. 19, 2020	Dec. 31, 2017	Mar. 31, 2020
One-Tier RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)			3.9
RSUs canceled (in shares)			3.3
Tranche One | One-Tier RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Co-Founder Grants | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		14.7	10.3
RSUs canceled (in shares)	4.4
Co-Founder Grants | Tranche One | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Chief Executive Officer | Co-Founder Grants | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		10.3
Director | Co-Founder Grants | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		4.4

Description of the Business a_7

Description of the Business and Summary of Significant Accounting Policies - Short-term Investments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Equity Investments	$ 20.6
Gain on equity investments	$ 11	$ 0

Description of the Business a_8

Description of the Business and Summary of Significant Accounting Policies - Concentration of Credit Risk (Details) - Trade and Other Receivables - Customer Concentration Risk	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Customer A
Concentration Risk [Line Items]
Concentration risk, percentage		10.00%
Customer B
Concentration Risk [Line Items]
Concentration risk, percentage	53.00%	27.00%

Description of the Business a_9

Description of the Business and Summary of Significant Accounting Policies - Deferred Commissions, Net (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Capitalized Contract Cost [Line Items]
Additional contract costs deferred	$ 7,800,000	$ 7,300,000
Deferred contract costs, amortization period	5 years
Amortization of deferred commissions	$ 5,100,000	$ 3,900,000
Impairment loss related to deferred costs	0
Deferred Commissions | Prepaid Expenses and Other Current Assets
Capitalized Contract Cost [Line Items]
Deferred contract costs	22,100,000		$ 19,900,000
Deferred Commissions | Other Assets
Capitalized Contract Cost [Line Items]
Deferred contract costs	$ 44,000,000		$ 43,500,000

Description of the Business _10

Description of the Business and Summary of Significant Accounting Policies - Property and Equipment, Net (Details)	3 Months Ended
	Mar. 31, 2020
Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Minimum | Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	20 years
Minimum | Datacenter and other computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Minimum | Office equipment and other
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	3 years
Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	7 years
Maximum | Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	30 years
Maximum | Datacenter and other computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	5 years
Maximum | Office equipment and other
Property, Plant and Equipment [Line Items]
Property and equipment, useful life	7 years

Cash, Cash Equivalents and Sh_3

Cash, Cash Equivalents and Short-Term Investments - Schedule of Components (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 486.4	$ 551.3
Total cash equivalents	486.4	551.3
Short-term investments, amortized cost	594.2	606.3
Short-term investments, unrealized gain	3	1.5
Short-term investments, unrealized loss	(3.4)	(0.1)
Total short-term investments	593.8	607.7
Cash and cash equivalents, amortized cost	1,080.6	1,157.6
Cash and cash equivalents, estimated fair value	1,080.2	1,159
Corporate notes and obligations
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	289	285.5
Short-term investments, unrealized gain	0.6	1.2
Short-term investments, unrealized loss	(2.7)	(0.1)
Total short-term investments	286.9	286.6
U.S. Treasury securities
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	173.3	171
Short-term investments, unrealized gain	2.1	0.3
Short-term investments, unrealized loss	0	0
Total short-term investments	175.4	171.3
Asset-backed securities
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	59.1	53.8
Short-term investments, unrealized gain	0.1	0
Short-term investments, unrealized loss	(0.7)	0
Total short-term investments	58.5	53.8
Certificates of deposit
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	30.8	38.2
Short-term investments, unrealized gain	0	0
Short-term investments, unrealized loss	0	0
Total short-term investments	30.8	38.2
Commercial Paper
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	21.4	24.2
Short-term investments, unrealized gain	0	0
Short-term investments, unrealized loss	0	0
Total short-term investments	21.4	24.2
U.S. agency obligations
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	15.3	27.2
Short-term investments, unrealized gain	0.2	0
Short-term investments, unrealized loss	0	0
Total short-term investments	15.5	27.2
Supranational securities
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	2.8	4
Short-term investments, unrealized gain	0	0
Short-term investments, unrealized loss	0	0
Total short-term investments	2.8	4
Municipal securities
Cash and Cash Equivalents [Line Items]
Short-term investments, amortized cost	2.5	2.4
Short-term investments, unrealized gain	0	0
Short-term investments, unrealized loss	0	0
Total short-term investments	2.5	2.4
Cash
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	112.1	105
Total cash equivalents	112.1	105
Money market funds
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	373	444.3
Total cash equivalents	373	444.3
Commercial Paper
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	1.3	2
Total cash equivalents	$ 1.3	$ 2

Cash, Cash Equivalents and Sh_4

Cash, Cash Equivalents and Short-Term Investments - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)investmentinvestment_type	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Cash and Cash Equivalents [Line Items]
Cash in transit for credit and debit card transactions	$ 11.8		$ 11.5
Short-term investments	$ 614.4
Number of investments in unrealized loss positions | investment	194
Short-Term Investments, Number of Security Types | investment_type	9
Short-Term Investments, Number of Security Types In Loss Position | investment_type	2
Investment income	$ (5.1)	$ (6.2)
Corporate notes and obligations
Cash and Cash Equivalents [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2.7
Asset-backed securities
Cash and Cash Equivalents [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	$ 0.7

Cash, Cash Equivalents and Sh_5

Cash, Cash Equivalents and Short-Term Investments - Contractual Maturities (Details) $ in Millions	Mar. 31, 2020USD ($)
Amortized cost
Due within one year	$ 288.3
Due between one to three years	280.8
Due after three years	25.1
Total	594.2
Estimated fair value
Due within one year	289.1
Due between one to three years	280.1
Due after three years	24.6
Total	$ 593.8

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	$ 486.4	$ 551.3
Total short-term investments	593.8	607.7
Equity Investments	20.6
Corporate notes and obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	286.9	286.6
U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	175.4	171.3
Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	58.5	53.8
Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	30.8	38.2
Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	21.4	24.2
U.S. agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	15.5	27.2
Supranational securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	2.8	4
Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	2.5	2.4
Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	373	444.3
Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	1.3	2
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	614.4	607.7
Total cash equivalents and short-term investments	988.7
Equity Investments		9.8
Total		1,063.8
Fair Value, Measurements, Recurring | Corporate notes and obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	286.9	286.6
Fair Value, Measurements, Recurring | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	175.4	171.3
Fair Value, Measurements, Recurring | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	58.5	53.8
Fair Value, Measurements, Recurring | Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	30.8	38.2
Fair Value, Measurements, Recurring | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	21.4	24.2
Fair Value, Measurements, Recurring | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	20.6
Fair Value, Measurements, Recurring | U.S. agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	15.5	27.2
Fair Value, Measurements, Recurring | Supranational securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	2.8	4
Fair Value, Measurements, Recurring | Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	2.5	2.4
Fair Value, Measurements, Recurring | Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	373	444.3
Fair Value, Measurements, Recurring | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	1.3	2
Fair Value, Measurements, Recurring | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	374.3	446.3
Fair Value, Measurements, Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	20.6	0
Total cash equivalents and short-term investments	393.6
Equity Investments		9.8
Total		454.1
Fair Value, Measurements, Recurring | Level 1 | Corporate notes and obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	20.6
Fair Value, Measurements, Recurring | Level 1 | U.S. agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Supranational securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 1 | Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	373	444.3
Fair Value, Measurements, Recurring | Level 1 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 1 | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	373	444.3
Fair Value, Measurements, Recurring | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	593.8	607.7
Total cash equivalents and short-term investments	595.1
Equity Investments		0
Total		609.7
Fair Value, Measurements, Recurring | Level 2 | Corporate notes and obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	286.9	286.6
Fair Value, Measurements, Recurring | Level 2 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	175.4	171.3
Fair Value, Measurements, Recurring | Level 2 | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	58.5	53.8
Fair Value, Measurements, Recurring | Level 2 | Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	30.8	38.2
Fair Value, Measurements, Recurring | Level 2 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	21.4	24.2
Fair Value, Measurements, Recurring | Level 2 | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0
Fair Value, Measurements, Recurring | Level 2 | U.S. agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	15.5	27.2
Fair Value, Measurements, Recurring | Level 2 | Supranational securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	2.8	4
Fair Value, Measurements, Recurring | Level 2 | Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	2.5	2.4
Fair Value, Measurements, Recurring | Level 2 | Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 2 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	1.3	2
Fair Value, Measurements, Recurring | Level 2 | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	1.3	2
Fair Value, Measurements, Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Total cash equivalents and short-term investments	0
Equity Investments		0
Total		0
Fair Value, Measurements, Recurring | Level 3 | Corporate notes and obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Certificates of deposit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0
Fair Value, Measurements, Recurring | Level 3 | U.S. agency obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Supranational securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring | Level 3 | Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 3 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 3 | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total cash equivalents	$ 0	$ 0

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Components (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,092.3	$ 1,032.5
Accumulated depreciation and amortization	(619.1)	(587.2)
Property and equipment, net	473.2	445.3
Datacenter and other computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	779	749.3
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	40	35.5
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	231.4	211.4
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 41.9	$ 36.3

Property and Equipment, Net - N

Property and Equipment, Net - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,092.3		$ 1,032.5
Accumulated depreciation	619.1		587.2
Depreciation	36	$ 43.1
Infrastructure Assets Acquired Under Finance Lease Agreements
Property, Plant and Equipment [Line Items]
Accumulated depreciation	129.9		124.6
Infrastructure Assets Held under Capital Leases
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 338.3		$ 321.8

Business Combinations - Schedul

Business Combinations - Schedule of Purchase Consideration (Details) - HelloSign Inc. $ in Millions	Feb. 08, 2019USD ($)
Business Acquisition [Line Items]
Fair value of assumed HelloSign options attributable to pre-combination services (1)	$ 0.8
Purchase price adjustments	(0.5)
Total purchase consideration	177.9
Preferred Stockholders and Vested Option Holders
Business Acquisition [Line Items]
Cash and transaction costs paid	175.2
HelloSign
Business Acquisition [Line Items]
Cash and transaction costs paid	$ 2.4

Business Combinations - Narrati

Business Combinations - Narrative (Details) - HelloSign Inc. - USD ($) $ in Millions	Feb. 08, 2019	Mar. 31, 2020	Mar. 31, 2019
Business Acquisition [Line Items]
Purchase consideration, agreements with key personnel	$ 48.5	$ 32.3
Required service period	3 years
Personnel agreement, expense recognized		$ 16.2
Acquired finite-lived intangible assets weighted average amortization period	4 years 10 months 24 days
Transaction costs			$ 1

Business Combinations - Assets

Business Combinations - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Feb. 08, 2019
Liabilities assumed:
Goodwill	$ 233.3	$ 234.5
HelloSign Inc.
Assets acquired:
Cash and cash equivalents			$ 5.5
Short-term investments			7.8
Acquisition-related intangible assets			44.6
Accounts receivable, prepaid and other assets			5
Total assets acquired			62.9
Liabilities assumed:
Accounts payable, accrued and other liabilities			6.3
Deferred revenue			4.8
Deferred tax liability			6.9
Total liabilities assumed			18
Net assets acquired, excluding goodwill			44.9
Total purchase consideration			177.9
Goodwill			$ 133

Business Combinations - Sched_2

Business Combinations - Schedule of Assets Acquired (Details) - HelloSign Inc. $ in Millions	Feb. 08, 2019USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair values	$ 44.6
Estimated weighted average useful lives (In years)	4 years 10 months 24 days
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair values	$ 20.5
Estimated weighted average useful lives (In years)	4 years 10 months 24 days
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair values	$ 19.6
Estimated weighted average useful lives (In years)	5 years
Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair values	$ 4.5
Estimated weighted average useful lives (In years)	5 years

Intangible Assets - Schedule of

Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 105.4	$ 105
Accumulated amortization	(61)	(57.6)
Intangible assets, net	44.4	47.4
Developed technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 25.7	25.8
Developed technology | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	3 years 9 months 18 days
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 20.5	20.5
Customer relationships | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	3 years 10 months 24 days
Software
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 20.5	20
Software | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	1 year 4 months 24 days
Patents
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 13	13
Patents | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	7 years 6 months
Assembled workforce in asset acquisitions
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 12.6	12.6
Assembled workforce in asset acquisitions | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	9 months 18 days
Trademarks and trade names
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 5.2	5.2
Trademarks and trade names | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	3 years 10 months 24 days
Licenses
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 4.6	4.6
Licenses | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	1 year 3 months 18 days
Other
Finite-Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 3.3	$ 3.3
Other | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted- average remaining useful life (In years)	5 years 4 months 24 days

Intangible Assets - Schedule _2

Intangible Assets - Schedule of Future Amortization Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 3.5	$ 2.8
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Remaining nine months of Fiscal 2020	10.7
2021	11.7
2022	8.3
2023	7.7
2024	3.4
Thereafter	2.6
Total	$ 44.4

Goodwill (Details)

Goodwill (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Beginning balance	$ 234,500,000
Effect of foreign currency translation	(1,200,000)
Ending balance	233,300,000	$ 234,500,000
Goodwill impairment	$ 0	$ 0

Revolving Credit Facility (Deta

Revolving Credit Facility (Details) - Credit And Guarantee Agreement - Line of Credit - USD ($)	Apr. 30, 2017	Apr. 30, 2019	Mar. 31, 2020	Feb. 28, 2018
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 600,000,000			$ 725,000,000
Debt issuance fees	$ 2,600,000			400,000
Debt instrument, term		5 years
Line of credit facility, accordion feature, increase limit				275,000,000
Unused capacity, commitment fee (percent)	0.20%
Covenant terms, minimum liquidity balance	$ 100,000,000
Aggregate letters of credit outstanding amount			$ 45,600,000
Remaining borrowing capacity			$ 679,400,000
Revolving Credit Facility | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)	1.50%
Revolving Credit Facility | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)	0.50%
Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity				$ 187,500,000
Commitment fee (percent)	1.50%
Fronting fee (percent)	0.125%

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Lessee, Lease, Description [Line Items]
Lease, renewal term	5 years
Sublease income	$ (1.8)	$ (1.9)
Minimum obligations	831.2
Tenant improvements	75
Tenant improvement allowance reimbursement	9.2	$ 13.8
Operating leases, not yet commenced, value	$ 116.9
Minimum
Lessee, Lease, Description [Line Items]
Lease, remaining lease term	1 year
Operating sublease, term	1 year
Operating leases, not yet commenced, term of contract	5 years
Maximum
Lessee, Lease, Description [Line Items]
Lease, remaining lease term	16 years
Operating sublease, term	4 years
Operating leases, not yet commenced, term of contract	15 years
Corporate Headquarters Lease
Lessee, Lease, Description [Line Items]
Tenant improvement allowance reimbursement	$ (8.5)
Line of Credit | Letter of Credit | Corporate Headquarters Lease
Lessee, Lease, Description [Line Items]
Letter of credit	$ 34.2

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Operating leases
2020 (excluding the three months ended March 31, 2020)	$ 91.3
2021	114.5
2022	107.1
2023	91.1
2024	84.7
Thereafter	644.1
Total future minimum lease payments	1,132.8
Less imputed interest	(254.1)
Less tenant improvement receivables	(22.9)
Operating lease, liability	855.8
Finance leases
2020 (excluding the three months ended March 31, 2020)	67.6
2021	78.1
2022	64
2023	30.4
2024	1.7
Thereafter	0
Total future minimum lease payments	241.8
Less imputed interest	(13.9)
Less tenant improvement receivables	0
Finance lease, liability	227.9
Rent payments from sub-tenants	$ 31.9
Minimum
Finance leases
Rent payments from sub-tenants, term	1 year
Maximum
Finance leases
Rent payments from sub-tenants, term	4 years

Commitments and Contingencies (

Commitments and Contingencies (Details)	Mar. 31, 2020lawsuit
Commitments and Contingencies Disclosure [Abstract]
Number of lawsuits	4

Accrued and Other Current Lia_3

Accrued and Other Current Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Non-income taxes payable	$ 93.3	$ 92.2
Accrued legal and other external fees	25.2	29.2
Other accrued and current liabilities	31	40.5
Total accrued and other current liabilities	$ 149.5	$ 161.9

Stockholders' Equity - Common S

Stockholders' Equity - Common Stock, Convertible Preferred Stock, Preferred Stock (Details)	1 Months Ended	3 Months Ended
	Dec. 31, 2017shares	Mar. 31, 2020vote$ / sharesshares	Mar. 31, 2019shares	Dec. 31, 2019shares
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)		240,000,000
Restricted Stock
Class of Stock [Line Items]
Shares granted (in shares)		3,900,000
Co-Founder Grants | Restricted Stock
Class of Stock [Line Items]
Shares granted (in shares)	14,700,000	10,300,000
Class A common stock
Class of Stock [Line Items]
Votes per share | vote		1
Common stock, shares authorized (in shares)		2,400,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.00001
Common stock, shares issued (in shares)		264,000,000		255,800,000
Common stock, shares outstanding (in shares)		264,000,000		255,800,000
Class B common stock
Class of Stock [Line Items]
Votes per share | vote		10
Shares converted in conversion (in shares)		9,900,000	11,800,000
Common stock, shares authorized (in shares)		475,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.00001
Common stock, shares issued (in shares)		151,300,000		161,200,000
Common stock, shares outstanding (in shares)		151,300,000		161,200,000
Class C common stock
Class of Stock [Line Items]
Votes per share | vote		0
Common stock, shares authorized (in shares)		800,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.00001
Common stock, shares issued (in shares)		0		0
Common stock, shares outstanding (in shares)		0		0

Stockholders' Equity - Stock Re

Stockholders' Equity - Stock Repurchase Program (Details) - USD ($) shares in Millions	3 Months Ended
	Mar. 31, 2020	Feb. 28, 2020
Stockholders' Equity Note [Abstract]
Stock repurchase program, authorized amount		$ 600,000,000
Stock repurchased and retired during period (in shares)	3.7
Stock repurchased and retired during period, aggregate purchase price	$ 64,000,000

Stockholders' Equity - Equity I

Stockholders' Equity - Equity Incentive Plans (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)
Shares issued and outstanding (in shares)	1.8		2
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of equity instruments other than options	$ 31.8	$ 67.9
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Remaining unamortized stock-based compensation	$ 600.1
Unamortized stock-based compensation, requisite service period	2 years 6 months
2018 Plan | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Vesting period	4 years
2008 Equity Incentive Plan, 2017 Equity Incentive Plan, and 2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued and outstanding (in shares)	30.4
Shares available for grant (in shares)	88.3

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Stock Option and Restricted Stock Activity (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2020	Dec. 31, 2019
Number of shares available for issuance under the Plans
Beginning balance (in shares)	66.2
Additional shares authorized (in shares)	21.7
Options and RSUs canceled (in shares)	3.3
Shares repurchased for tax withholdings on release of restricted stock (unaudited) (in shares)	1
Restricted stock granted (in shares)	(3.9)
Ending balance (in shares)	88.3	66.2
Options Outstanding, Number of shares outstanding under the Plans
Beginning balance (in shares)	2
Options exercised (in shares)	(0.1)
Options canceled (in shares)	(0.1)
Options granted (in shares)
Ending balance (in shares)	1.8	2
Vested during period (in shares)	1.2
Unvested at end of period (in shares)			0.6
Options Outstanding, Weighted- average exercise price per share
Beginning balance (in dollars per share)	$ 12.28
Options exercised (in dollars per share)	5.43
Options canceled (in dollars per share)	23.38
Options granted (in dollars per share)
Ending balance (in dollars per share)	12.36	$ 12.28
Vested during period (in dollars per share)	$ 15.40
Unvested at end of period (in dollars per shares)			$ 5.26
Options Outstanding, Weighted- average remaining contractual term (In years)
Weighted-average contractual term	6 years 3 months 18 days	6 years 6 months
Vested during period	5 years 6 months
Options outstanding, aggregate intrinsic value			$ 12,900	$ 16,400
Vested during period, aggregate intrinsic value			6,400
Unvested during period, aggregate intrinsic value			$ 6,500
Restricted Stock
Restricted Stock Outstanding, Number of Plan shares outstanding
Beginning balance (in shares)	30.7
RSUs released (in shares)	(2.7)
RSUs canceled (in shares)	(3.3)
Restricted stock granted (in shares)	3.9
Ending balance (in shares)	28.6	30.7
Vested during period (in shares)	0
Unvested at end of period (in shares)	28.6	30.7	28.6	30.7
Restricted Stock Outstanding, Weighted- average grant date fair value per share
Beginning balance (in dollars per share)	$ 20.48
RSUs released (in dollars per share)	20.20
RSUs canceled (in dollars per share)	20.51
Shares repurchased for tax withholdings on release of restricted stock (in dollars per share)	20.19
Restricted stock granted (in dollars per share)	18.59
Ending balance (in dollars per share)	20.25	$ 20.48
Vested during period (in dollars per share)	0
Unvested at end of period (in dollars per share)	$ 20.25	$ 20.48	$ 20.25	$ 20.48

Stockholders' Equity - Schedu_2

Stockholders' Equity - Schedule of Pre-Tax Intrinsic Value (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Stockholders' Equity Note [Abstract]
Intrinsic value of options exercised	$ 1.8	$ 3.1

Stockholders' Equity - Assumed

Stockholders' Equity - Assumed Stock Options (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	Feb. 08, 2019	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield		0.00%
Weighted average grant date fair value of stock options assumed (in dollars per share)		$ 21.60
Fair value of options assumed in business combination		$ 19.4
Post combination, stock-based compensation expense		$ 18.6
HelloSign Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options assumed (in shares)	0.9

Stockholders' Equity - Fair Val

Stockholders' Equity - Fair Value of Stock Option Assumptions Used (Details)	3 Months Ended
	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	51.60%
Risk-free interest rate, minimum	2.42%
Risk-free interest rate, maximum	2.51%
Dividend yield	0.00%
Employee Stock Option | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	3 years 4 months 24 days
Employee Stock Option | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	7 years

Stockholders' Equity - Co-Found

Stockholders' Equity - Co-Founder Grants and Award Modifications (Details) $ / shares in Units, shares in Millions, $ in Millions	Mar. 19, 2020USD ($)shares	Dec. 31, 2017shares	Mar. 31, 2020USD ($)$ / sharesshares	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)tranche$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) | $ / shares			$ 5.26
Reversal of stock based compensation expense | $	$ 23.8		$ 23.8
Reversal of stock based compensation previously recognized | $	$ 21.5
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)			3.9
RSUs canceled (in shares)			3.3
Co-Founder Grants | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		14.7	10.3
Expiration period		10 years
Number of tranches | tranche					9
Weighted average grant date fair value (in dollars per share) | $ / shares					$ 10.60
Unamortized stock-based compensation, requisite service period				5 years 2 months 12 days
Remaining unamortized stock-based compensation | $			$ 52.9		$ 156.2
RSUs canceled (in shares)	4.4
Stock-based compensation related to the Co-Founder Grants | $			$ 6.1	$ 8.6
Co-Founder Grants | Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation, requisite service period				2 years 10 months 24 days
Co-Founder Grants | Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation, requisite service period				6 years 10 months 24 days
Co-Founder Grants | Restricted Stock | Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Co-Founder Grants | Restricted Stock | Tranche One | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vested maximum		20.00%
Co-Founder Grants | Chief Executive Officer | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		10.3
Co-Founder Grants | Director | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		4.4

Net Income (Loss) Per Share - S

Net Income (Loss) Per Share - Schedule of EPS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share, Basic [Abstract]
Net income (loss) attributable to common stockholders	$ 39.3	$ (7.7)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	417.3	410.5
Net income (loss) per share attributable to common stockholders, basic (in dollars per share)	$ 0.09	$ (0.02)
Earnings Per Share, Diluted [Abstract]
Net income (loss) attributable to common stockholders	$ 39.3	$ (7.7)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	417.3	410.5
Weighted-average shares used in computing net loss per share attributable to common stockholders,diluted (in shares)	419.3	410.5
Net income (loss) per share attributable to common stockholders, diluted (in dollars per share)	$ 0.09	$ (0.02)
Class A
Earnings Per Share, Basic [Abstract]
Net income (loss) attributable to common stockholders	$ 24.5	$ (4)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	260	215.1
Net income (loss) per share attributable to common stockholders, basic (in dollars per share)	$ 0.09	$ (0.02)
Earnings Per Share, Diluted [Abstract]
Net income (loss) attributable to common stockholders	$ 24.5	$ (4)
Reallocation of net income as a result of conversion of Class B to Class A common stock	14.8	0
Net income (loss) attributable to common stockholders for diluted EPS	$ 39.3	$ (4)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	260	215.1
Weighted-average effect of dilutive RSUs and employee stock options (in shares)	1.6	0
Conversion of Class B to Class A common stock (in shares)	157.3	0
Weighted-average shares used in computing net loss per share attributable to common stockholders,diluted (in shares)	418.9	215.1
Net income (loss) per share attributable to common stockholders, diluted (in dollars per share)	$ 0.09	$ (0.02)
Class B
Earnings Per Share, Basic [Abstract]
Net income (loss) attributable to common stockholders	$ 14.8	$ (3.7)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	157.3	195.4
Net income (loss) per share attributable to common stockholders, basic (in dollars per share)	$ 0.09	$ (0.02)
Earnings Per Share, Diluted [Abstract]
Net income (loss) attributable to common stockholders	$ 14.8	$ (3.7)
Reallocation of net income as a result of conversion of Class B to Class A common stock	0	0
Net income (loss) attributable to common stockholders for diluted EPS	$ 14.8	$ (3.7)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	157.3	195.4
Weighted-average effect of dilutive RSUs and employee stock options (in shares)	0.4	0
Conversion of Class B to Class A common stock (in shares)	0	0
Weighted-average shares used in computing net loss per share attributable to common stockholders,diluted (in shares)	157.7	195.4
Net income (loss) per share attributable to common stockholders, diluted (in dollars per share)	$ 0.09	$ (0.02)

Net Income (Loss) Per Share -_2

Net Income (Loss) Per Share - Schedule of Potentially Dilutive Securities Excluded from Computation (Details) - shares shares in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	30.9	41.1
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	15.2	24.6
Restricted stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0.2	0
Options to purchase shares of common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	1.3	1.8
Co-Founder Grants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	14.2	14.7

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 0.5	$ (5.7)
Increase in unrecognized tax benefits	3.5
Unrecognized tax benefits that would impact effective tax rate	0.4
Decrease in unrecognized tax benefits for expiration of statute of limitations	$ 0.2

Geographic Areas (Details)

Geographic Areas (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Property and equipment, net	$ 473.2		$ 445.3
Revenue	455	$ 385.6
United States
Segment Reporting Information [Line Items]
Property and equipment, net	461.3		431.9
Revenue	235.6	197.1
International
Segment Reporting Information [Line Items]
Property and equipment, net	11.9		$ 13.4
Revenue	$ 219.4	$ 188.5

Uncategorized Items - dbx-03302

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 1,000,000
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 1,000,000