Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements and condensed footnotes have been prepared in accordance with the applicable rules and regulations of the Securities and Exchange Commission (the “SEC”) regarding interim financial reporting. Accordingly, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles (“GAAP”) for complete financial statements due to the permitted exclusion of certain disclosures for interim reporting. In the opinion of management, all adjustments (consisting of normal recurring items) considered necessary under GAAP for fair statement of results for the interim periods presented have been included. The results of operations for the three and nine months ended September 30, 2020 are not necessarily indicative of the results to be expected for the year ending December 31, 2020 or for other interim periods or future years. The condensed consolidated balance sheet as of December 31, 2019 is derived from audited financial statements; however, it does not include all of the information and footnotes required by GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2019, which was filed with the SEC on February 20, 2020.
Principles of Consolidation	Principles of Consolidation The condensed consolidated financial statements have been prepared in conformity with GAAP, and include our accounts and the accounts of our wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated upon consolidation.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make certain estimates and assumptions. These estimates and assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, as well as reported amounts of revenues and expenses during the reporting period. Such management estimates and assumptions include, but are not limited to, evaluating the terms and conditions included within our customer contracts as well as determining the standalone selling price for each distinct performance obligation included in customer contracts with multiple performance obligations, the period of benefit for deferred commissions, purchase price allocation for business combinations, stock-based compensation, the useful life of our property and equipment, goodwill and identifiable intangible assets, whether an arrangement is or contains a lease, the discount rate used for operating leases, fair value of convertible notes and income taxes. Actual results could differ from those estimates.
Investments	Investments Investments consist of commercial paper, corporate notes and bonds, certificates of deposit and U.S. government and agency securities. We classify investments as available-for-sale at the time of purchase and re-evaluate such classification as of each balance sheet date. All investments are recorded at estimated fair value. Unrealized gains and losses for available-for-sale securities are included in accumulated other comprehensive income, net of tax, a component of stockholders’ equity, except for credit-related impairment losses for available-for-sale debt securities. We evaluate our investments with unrealized loss positions for other than temporary impairment by assessing if they are related to deterioration in credit risk and whether we expect to recover the entire amortized cost basis of the security, our intent to sell and whether it is more likely than not that we will be required to sell the securities before the recovery of their cost basis. Credit-related impairment losses, not to exceed the amount that fair value is less than the amortized cost basis, are recognized through an allowance for credit losses with changes in the allowance for credit losses recorded in interest income and other income, net in the condensed consolidated statements of comprehensive income. For purposes of identifying and measuring impairment, the policy election was made to exclude the applicable accrued interest from both the fair value and amortized cost basis. Applicable accrued interest, net of the allowance for credit losses (if any) of $13 million and $11 million, is recorded in prepaid expenses and other current assets on the condensed consolidated balance sheets as of September 30, 2020 and December 31, 2019, respectively. Realized gains and losses and declines in value judged to be other than temporary are determined based on the specific identification method and are reported in interest income and other income (expense), net in the condensed consolidated statements of comprehensive income.
Goodwill	Goodwill We evaluate and test the recoverability of goodwill for impairment at least annually or more frequently if circumstances indicate that goodwill may not be recoverable. We changed the timing of our annual assessment from fourth quarter to third quarter. The Company does not consider this change to be material. We believe the change in timing is preferable as it better aligns with the Company’s closing processes and create efficiency. This change did not delay, accelerate or avoid any impairment charge.
Accounts Receivable	Accounts Receivable We record trade accounts receivable at the net invoice value and such receivables are non-interest bearing. We consider receivables past due based on the contractual payment terms. We review our exposure to accounts receivable and reserve for specific amounts if collectibility is no longer reasonably assured based on assessment of various factors including historical loss rates and expectations of forward-looking loss estimates.
Concentration of Credit Risk and Significant Customers	Concentration of Credit Risk and Significant CustomersCredit risk arising from accounts receivable is mitigated to a certain extent due to our large number of customers and their dispersion across various industries and geographies. As of September 30, 2020, we had one customer, a channel partner, that represented 21% of our accounts receivable balance and no customers that individually exceeded 10% of our total revenues in any of the periods presented. As of December 31, 2019, there were no customers that represented more than 10% of our accounts receivable balance. For purposes of assessing concentration of credit risk and significant customers, a group of customers under common control or customers that are affiliates of each other are regarded as a single customer.
Accounting Pronouncements Adopted in 2020, Accounting Pronouncement Adopted in 2019, and Recently Issued Accounting Pronouncement Pending Adoption	Accounting Pronouncements Adopted in 2020 Cloud computing arrangements implementation costs In August 2018, the Financial Accounting Standards Board (“FASB”) issued ASU 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,” which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The new standard requires capitalized costs to be amortized on a straight-line basis generally over the term of the arrangement, and the financial statement presentation for these capitalized costs would be the same as that of the fees related to the hosting arrangements. We adopted this standard on a prospective basis as of January 1, 2020. The adoption of this standard did not have a material impact on our previously reported consolidated financial statements for periods ended on or prior to December 31, 2019. Credit losses In June 2016, the FASB issued ASU 2016-13, “Financial Instruments-Credit Losses (“Topic 326”): Measurement of Credit Losses on Financial Instruments,” which requires a financial asset measured at amortized cost basis to be presented at the net amount expected to be collected, with further clarifications made more recently regarding the treatment of accrued interest, transfers between classifications for loans and debt securities, recoveries and the option to irrevocably elect the fair value option (on an instrument-by-instrument basis) for eligible financial assets at amortized costs. For trade receivables, loans, and other financial assets, we will be required to use a forward-looking expected loss model rather than the incurred loss model for recognizing credit losses which reflects losses that are probable. Credit losses relating to available-for-sale debt securities are required to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. We adopted Topic 326 on a modified retrospective basis as of January 1, 2020. The adoption of this standard did not result in any cumulative effect adjustment on our condensed consolidated financial statements upon adoption as of January 1, 2020. Accounting Pronouncement Adopted in 2019 Leases In February 2016, the FASB issued ASU 2016-02, “Leases (“Topic 842”),” which requires lessees to generally recognize on the balance sheet operating and financing lease liabilities and corresponding right-of-use assets, and to recognize on the income statement the expenses in a manner similar to prior practice. We adopted Topic 842 using the modified retrospective method as of January 1, 2019 and elected the transition option that allows us not to restate the comparative periods in our financial statements in the year of adoption. We also elected the package of transition expedients available for expired or existing contracts, which allowed us to carryforward our historical assessment of (1) whether contracts are or contain leases, (2) lease classification and (3) initial direct costs. As this standard was adopted on a modified prospective basis as of January 1, 2019, the adoption of this standard did not impact our previously reported consolidated financial statements for periods ended on or prior to December 31, 2018. Upon adoption, we recorded operating lease right-of-use assets of $335 million and corresponding operating lease liabilities of $363 million on our condensed consolidated balance sheets. Recently Issued Accounting Pronouncement Pending Adoption Debt with Conversion Options In August 2020, the FASB issued new guidance to simplify the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. The standard eliminates beneficial conversion feature and cash conversion models resulting in more convertible instruments being accounted for as a single unit; and simplifies classification of debt on the balance sheet and earnings per share calculation. This new standard is effective for our interim and annual periods beginning January 1, 2022 and earlier adoption is permitted. Amendments within this standard are required to be applied on a retrospective or modified retrospective basis. We are currently evaluating the impact of the adoption of this standard on our condensed consolidated financial statements. Income taxes In December 2019, the FASB issued ASU 2019-12, “Income Taxes (“Topic 740”): Simplifying the Accounting for Income Taxes,” which simplifies the accounting for incomes taxes by removing certain exceptions to the general principles in Topic 740 and amending existing guidance to improve consistent application. This new standard is effective for our interim and annual periods beginning January 1, 2021 and earlier adoption is permitted. Most amendments within this standard are required to be applied on a prospective basis, while certain amendments must be applied on a retrospective or modified retrospective basis. We expect the adoption of the standard will change the methodology of how we allocate interim period tax expense throughout an annual period. We are currently evaluating the impact of the adoption of this standard on our condensed consolidated financial statements.
Fair Value Measurements	We determine the fair value of our security holdings based on pricing from our service providers and market prices from industry-standard independent data providers. Such market prices may be quoted prices in active markets for identical assets (Level 1 inputs) or pricing determined using inputs other than quoted prices that are observable either directly or indirectly (Level 2 inputs), such as yield curve, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments or debt, broker and dealer quotes, as well as other relevant economic measures.Our equity investments in privately-held companies are not included in the table above and are discussed in Note 3.
Legal Proceedings	From time to time, we are party to litigation and other legal proceedings in the ordinary course of business. While the results of any litigation or other legal proceedings are uncertain, management does not believe the ultimate resolution of any pending legal matters is likely to have a material adverse effect on our financial position, results of operations or cash flows, except for those matters for which we have recorded a loss contingency. We accrue for loss contingencies when it is both probable that we will incur the loss and when we can reasonably estimate the amount of the loss or range of loss. Generally, our subscription agreements require us to defend our customers for third-party intellectual property infringement and other claims. Any adverse determination related to intellectual property claims or other litigation could prevent us from offering our services and adversely affect our financial condition and results of operations.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2020

The accompanying unaudited condensed consolidated financial statements and condensed footnotes have been prepared in accordance with the applicable rules and regulations of the Securities and Exchange Commission (the “SEC”) regarding interim financial reporting. Accordingly, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles (“GAAP”) for complete financial statements due to the permitted exclusion of certain disclosures for interim reporting. In the opinion of management, all adjustments (consisting of normal recurring items) considered necessary under GAAP for fair statement of results for the interim periods presented have been included. The results of operations for the three and nine months ended September 30, 2020 are not necessarily indicative of the results to be expected for the year ending December 31, 2020 or for other interim periods or future years. The condensed consolidated balance sheet as of December 31, 2019 is derived from audited financial statements; however, it does not include all of the information and footnotes required by GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in our Annual Report on Form 10-K for the year ended December 31, 2019, which was filed with the SEC on February 20, 2020.

Principles of Consolidation

The condensed consolidated financial statements have been prepared in conformity with GAAP, and include our accounts and the accounts of our wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated upon consolidation.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make certain estimates and assumptions. These estimates and assumptions affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements, as well as reported amounts of revenues and expenses during the reporting period. Such management estimates and assumptions include, but are not limited to, evaluating the terms and conditions included within our customer contracts as well as determining the standalone selling price for each distinct performance obligation included in customer contracts with multiple performance obligations, the period of benefit for deferred commissions, purchase price allocation for business combinations, stock-based compensation, the useful life of our property and equipment, goodwill and identifiable intangible assets, whether an arrangement is or contains a lease, the discount rate used for operating leases, fair value of convertible notes and income taxes. Actual results could differ from those estimates.

Investments

Investments consist of commercial paper, corporate notes and bonds, certificates of deposit and U.S. government and agency securities. We classify investments as available-for-sale at the time of purchase and re-evaluate such classification as of each balance sheet date. All investments are recorded at estimated fair value. Unrealized gains and losses for available-for-sale securities are included in accumulated other comprehensive income, net of tax, a component of stockholders’ equity, except for credit-related impairment losses for available-for-sale debt securities.

We evaluate our investments with unrealized loss positions for other than temporary impairment by assessing if they are related to deterioration in credit risk and whether we expect to recover the entire amortized cost basis of the security, our intent to sell and whether it is more likely than not that we will be required to sell the securities before the recovery of their cost basis. Credit-related impairment losses, not to exceed the amount that fair value is less than the amortized cost basis, are recognized through an allowance for credit losses with changes in the allowance for credit losses recorded in interest income and other income, net in the condensed consolidated statements of comprehensive income. For purposes of identifying and measuring impairment, the policy election was made to exclude the applicable accrued interest from both the fair value and amortized cost basis. Applicable accrued interest, net of the allowance for credit losses (if any) of $13 million and $11 million, is recorded in prepaid expenses and other current assets on the condensed consolidated balance sheets as of September 30, 2020 and December 31, 2019, respectively.

Realized gains and losses and declines in value judged to be other than temporary are determined based on the specific identification method and are reported in interest income and other income (expense), net in the condensed consolidated statements of comprehensive income.

Goodwill

We evaluate and test the recoverability of goodwill for impairment at least annually or more frequently if circumstances indicate that goodwill may not be recoverable. We changed the timing of our annual assessment from fourth quarter to third quarter. The Company does not consider this change to be material. We believe the change in timing is preferable as it better aligns with the Company’s closing processes and create efficiency. This change did not delay, accelerate or avoid any impairment charge.

Accounts Receivable

We record trade accounts receivable at the net invoice value and such receivables are non-interest bearing. We consider receivables past due based on the contractual payment terms. We review our exposure to accounts receivable and reserve for specific amounts if collectibility is no longer reasonably assured based on assessment of various factors including historical loss rates and expectations of forward-looking loss estimates.

Concentration of Credit Risk and Significant Customers

Concentration of Credit Risk and Significant CustomersCredit risk arising from accounts receivable is mitigated to a certain extent due to our large number of customers and their dispersion across various industries and geographies. As of September 30, 2020, we had one customer, a channel partner, that represented 21% of our accounts receivable balance and no customers that individually exceeded 10% of our total revenues in any of the periods presented. As of December 31, 2019, there were no customers that represented more than 10% of our accounts receivable balance. For purposes of assessing concentration of credit risk and significant customers, a group of customers under common control or customers that are affiliates of each other are regarded as a single customer.

Accounting Pronouncements Adopted in 2020, Accounting Pronouncement Adopted in 2019, and Recently Issued Accounting Pronouncement Pending Adoption

Accounting Pronouncements Adopted in 2020

Cloud computing arrangements implementation costs

In August 2018, the Financial Accounting Standards Board (“FASB”) issued ASU 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,” which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The new standard requires capitalized costs to be amortized on a straight-line basis generally over the term of the arrangement, and the financial statement presentation for these capitalized costs would be the same as that of the fees related to the hosting arrangements. We adopted this standard on a prospective basis as of January 1, 2020. The adoption of this standard did not have a material impact on our previously reported consolidated financial statements for periods ended on or prior to December 31, 2019.

Credit losses

In June 2016, the FASB issued ASU 2016-13, “Financial Instruments-Credit Losses (“Topic 326”): Measurement of Credit Losses on Financial Instruments,” which requires a financial asset measured at amortized cost basis to be presented at the net amount expected to be collected, with further clarifications made more recently regarding the treatment of accrued interest, transfers between classifications for loans and debt securities, recoveries and the option to irrevocably elect the fair value option (on an instrument-by-instrument basis) for eligible financial assets at amortized costs. For trade receivables, loans, and other financial assets, we will be required to use a forward-looking expected loss model rather than the incurred loss model for recognizing credit losses which reflects losses that are probable. Credit losses relating to available-for-sale debt securities are required to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. We adopted Topic 326 on a modified retrospective basis as of January 1, 2020. The adoption of this standard did not result in any cumulative effect adjustment on our condensed consolidated financial statements upon adoption as of January 1, 2020.

Accounting Pronouncement Adopted in 2019

Leases

In February 2016, the FASB issued ASU 2016-02, “Leases (“Topic 842”),” which requires lessees to generally recognize on the balance sheet operating and financing lease liabilities and corresponding right-of-use assets, and to recognize on the income statement the expenses in a manner similar to prior practice. We adopted Topic 842 using the modified retrospective method as of January 1, 2019 and elected the transition option that allows us not to restate the comparative periods in our financial statements in the year of adoption. We also elected the package of transition expedients available for expired or existing contracts, which allowed us to carryforward our historical assessment of (1) whether contracts are or contain leases, (2) lease classification and (3) initial direct costs. As this standard was adopted on a modified prospective basis as of January 1, 2019, the adoption of this standard did not impact our previously reported consolidated financial statements for periods ended on or prior to December 31, 2018. Upon adoption, we recorded operating lease right-of-use assets of $335 million and corresponding operating lease liabilities of $363 million on our condensed consolidated balance sheets.

Recently Issued Accounting Pronouncement Pending Adoption

Debt with Conversion Options

In August 2020, the FASB issued new guidance to simplify the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. The standard eliminates beneficial conversion feature and cash conversion models resulting in more convertible instruments being accounted for as a single unit; and simplifies classification of debt on the balance sheet and earnings per share calculation. This new standard is effective for our interim and annual periods beginning January 1, 2022 and earlier adoption is permitted. Amendments within this standard are required to be applied on a retrospective or modified retrospective basis. We are currently evaluating the impact of the adoption of this standard on our condensed consolidated financial statements.

Income taxes

In December 2019, the FASB issued ASU 2019-12, “Income Taxes (“Topic 740”): Simplifying the Accounting for Income Taxes,” which simplifies the accounting for incomes taxes by removing certain exceptions to the general principles in Topic 740 and amending existing guidance to improve consistent application. This new standard is effective for our interim and annual periods beginning January 1, 2021 and earlier adoption is permitted. Most amendments within this standard are required to be applied on a prospective basis, while certain amendments must be applied on a retrospective or modified retrospective basis. We expect the adoption of the standard will change the methodology of how we allocate interim period tax expense throughout an annual period. We are currently evaluating the impact of the adoption of this standard on our condensed consolidated financial statements.

Fair Value Measurements

We determine the fair value of our security holdings based on pricing from our service providers and market prices from industry-standard independent data providers. Such market prices may be quoted prices in active markets for identical assets (Level 1 inputs) or pricing determined using inputs other than quoted prices that are observable either directly or indirectly (Level 2 inputs), such as yield curve, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments or debt, broker and dealer quotes, as well as other relevant economic measures.Our equity investments in privately-held companies are not included in the table above and are discussed in Note 3.

Legal Proceedings

From time to time, we are party to litigation and other legal proceedings in the ordinary course of business. While the results of any litigation or other legal proceedings are uncertain, management does not believe the ultimate resolution of any pending legal matters is likely to have a material adverse effect on our financial position, results of operations or cash flows, except for those matters for which we have recorded a loss contingency. We accrue for loss contingencies when it is both probable that we will incur the loss and when we can reasonably estimate the amount of the loss or range of loss.

Generally, our subscription agreements require us to defend our customers for third-party intellectual property infringement and other claims. Any adverse determination related to intellectual property claims or other litigation could prevent us from offering our services and adversely affect our financial condition and results of operations.