Basis of presentation and summary of significant accounting policies (Policies)	9 Months Ended
Sep. 30, 2024
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation The Company’s condensed consolidated financial statements are presented in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and reflect the financial position, results of operations and cash flows for all periods presented. The year-end condensed balance sheet data was derived from audited financial statements but does not include all disclosures required by U.S. GAAP. The accompanying interim Condensed Consolidated Balance Sheets as of September 30, 2024, the Condensed Consolidated Statements of Operations and Comprehensive Income (Loss), of Cash Flows and of Changes in Stockholders’ Equity for the three and nine months ended September 30, 2024 and 2023, and the related footnote disclosures are unaudited. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and, in management’s opinion, include all adjustments necessary to state fairly the consolidated financial position of the Company. All adjustments made were of a normal recurring nature. The results for the three and nine months ended September 30, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024, or for any future period. The Company’s significant accounting policies are discussed in Note 2 to the consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023, filed with the Securities and Exchange Commission (“SEC”) on February 27, 2024 (the "2023 Form 10-K") and these unaudited condensed consolidated financial statements should be read in conjunction with the 2023 Form 10-K.
Basis of consolidation	Basis of consolidation The condensed consolidated financial statements include the accounts of Integral Ad Science Holding Corp. and its wholly-owned subsidiaries. All material intercompany accounts and transactions have been eliminated in consolidation.
Use of estimates	Use of estimatesThe preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from these estimates. Significant estimates include the estimated useful lives of intangible assets and internal use software, the allowance for credit losses, goodwill impairment testing, assumptions used to calculate equity-based compensation, and the realization of deferred tax assets. The Company bases its estimates on past experience, market conditions, and other assumptions that the Company believes are reasonable under the circumstances, and the Company evaluates these estimates on an ongoing basis. Actual results may differ from these estimates due to risks and uncertainties, including the continued uncertainty surrounding the stability of economic conditions due to high inflation, changes to fiscal and monetary policy, high interest rates, currency fluctuations, fluctuations in the financial markets and disruptions in European economies as a result of the war in Ukraine and other geopolitical issues.
Foreign currency	Foreign currencyThe reporting currency of the Company is the U.S. dollar. The functional currency of our foreign subsidiaries is the currency of the primary economic environment in which they operate, which is their local currency. The financial statements of these subsidiaries are translated into U.S. dollars using month-end rates of exchange for assets and liabilities, and average rates of exchange for revenue, costs and expenses. Translation gains and losses are recorded in accumulated other comprehensive loss within stockholders’ equity. Transaction gains and losses including those on intercompany transactions denominated in a currency other than the functional currency of the entity involved are included in foreign exchange (gain) loss, net in the Condensed Consolidated Statements of Operations and Comprehensive Income (Loss).
Cash, cash equivalents, and restricted cash	Cash, cash equivalents, and restricted cash Cash equivalents include money market accounts and other highly liquid investments with an original maturity date of three months or less at the time of purchase. Cash amounts with restrictions are classified as restricted cash within the Condensed Consolidated Balance Sheets.
Accounts receivable, net	Accounts receivable, net Accounts receivable are carried at the original invoiced amount less an allowance for credit losses. The allowance is estimated by pooling accounts receivables based on similar risk characteristics, and expected credit loss exposure is evaluated for each accounts receivable pool. Invoices are typically issued with net 30-days to net 90-days terms. Account balances are considered delinquent if payment is not received by the due date, and the receivables are written off when deemed uncollectible. These costs are recorded in general and administrative expenses within the Condensed Consolidated Statements of Operations and Comprehensive Income (Loss).
Stock-based compensation	Stock-based compensation Stock-based compensation is measured at the grant date based on the fair value of the award and is recognized as expense over the requisite service period, which is generally the vesting period. The Company accounts for forfeitures as they occur. The Company used the following assumptions in valuing its market stock units ("MSUs"), shares granted under the Company's 2021 Employee Stock Purchase Program ("ESPP"), time-based service options, which vest over a period of time subject to continued employment ("Time-Based Options"), and return-target options ("Return-Target Options"), which vest upon a realized cash return of the equity investment of funds affiliated with Vista Equity Partners ("Vista"), the Company’s largest shareholder. Expected term — For time-based awards, the estimated expected term of options granted is generally calculated as the vesting period plus the midpoint of the remaining contractual term, as the Company does not have sufficient historical information to develop reasonable expectations surrounding future exercise patterns and post-vesting employment termination behavior. For awards subject to market and performance conditions, the expected term represents the period of time that the options granted are expected to be outstanding. Expected volatility — Volatility is estimated based upon observed option-implied volatilities for the Company in addition to a group of peer companies. The Company believes this is the best estimate of the expected volatility over the weighted-average expected term of its option grants. Risk-free interest rate — The risk-free interest rate is based on the implied yield currently available on U.S. Treasury instruments with terms approximately equal to the expected term of the option. Expected dividend — The expected dividend assumption was based on the Company’s history and expectation of dividend payouts. The Company currently has no history or expectation of paying cash dividends on its common stock. Fair value — Following the pricing of the Initial Public Offering, the Company’s shares have traded publicly, and accordingly the Company uses the applicable closing price of its common stock to determine fair value.
Accounting pronouncements not yet adopted	(h) Accounting pronouncements not yet adopted On November 27, 2023, the FASB issued ASU 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures," which requires incremental disclosures related to an entity's reportable segments. This ASU is effective for annual periods beginning after December 15, 2023. The Company does not expect the adoption of ASU 2023-07 to have a material impact on its consolidated financial statements. On December 14, 2023, the FASB issued ASU 2023-09, "Income Taxes (Topic 740): Improvements to Income Tax Disclosures," which requires companies to disclose more detailed information in their reconciliation of their statutory tax rate to their effective tax rate. The ASU also requires entities to disclosure more detailed information about income taxes paid, including by jurisdiction, pretax income (or loss) from continuing operations and income tax expense (or benefit). This ASU is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2024. The Company is currently evaluating the impact of the adoption of ASU No. 2023-09 on its consolidated financial statements. In March 2024, the Securities and Exchange Commission issued Final Rule No. 33-11275, "The Enhancement and Standardization of Climate-Related Disclosures for Investors," that would require registrants to disclose climate-related information in registration statements and annual reports on Form 10-K. In April 2024, given pending legal challenges, the Securities and Exchange Commission issued an order to voluntarily stay the new rules. The Company is currently evaluating the potential impact of the rule on its consolidated financial statements.

Basis of presentation and summary of significant accounting policies (Policies)

9 Months Ended

Sep. 30, 2024

The Company’s condensed consolidated financial statements are presented in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and reflect the financial position, results of operations and cash flows for all periods presented. The year-end condensed balance sheet data was derived from audited financial statements but does not include all disclosures required by U.S. GAAP.

The accompanying interim Condensed Consolidated Balance Sheets as of September 30, 2024, the Condensed Consolidated Statements of Operations and Comprehensive Income (Loss), of Cash Flows and of Changes in Stockholders’ Equity for the three and nine months ended September 30, 2024 and 2023, and the related footnote disclosures are unaudited. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and, in management’s opinion, include all adjustments necessary to state fairly the consolidated financial position of the Company. All adjustments made were of a normal recurring nature. The results for the three and nine months ended September 30, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024, or for any future period.

The Company’s significant accounting policies are discussed in Note 2 to the consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2023, filed with the Securities and Exchange Commission (“SEC”) on February 27, 2024 (the "2023 Form 10-K") and these unaudited condensed consolidated financial statements should be read in conjunction with the 2023 Form 10-K.

Basis of consolidation

The condensed consolidated financial statements include the accounts of Integral Ad Science Holding Corp. and its wholly-owned subsidiaries. All material intercompany accounts and transactions have been eliminated in consolidation.

Use of estimates

Use of estimatesThe preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from these estimates. Significant estimates include the estimated useful lives of intangible assets and internal use software, the allowance for credit losses, goodwill impairment testing, assumptions used to calculate equity-based compensation, and the realization of deferred tax assets. The Company bases its estimates on past experience, market conditions, and other assumptions that the Company believes are reasonable under the circumstances, and the Company evaluates these estimates on an ongoing basis. Actual results may differ from these estimates due to risks and uncertainties, including the continued uncertainty surrounding the stability of economic conditions due to high inflation, changes to fiscal and monetary policy, high interest rates, currency fluctuations, fluctuations in the financial markets and disruptions in European economies as a result of the war in Ukraine and other geopolitical issues.

Foreign currency

Foreign currencyThe reporting currency of the Company is the U.S. dollar. The functional currency of our foreign subsidiaries is the currency of the primary economic environment in which they operate, which is their local currency. The financial statements of these subsidiaries are translated into U.S. dollars using month-end rates of exchange for assets and liabilities, and average rates of exchange for revenue, costs and expenses. Translation gains and losses are recorded in accumulated other comprehensive loss within stockholders’ equity. Transaction gains and losses including those on intercompany transactions denominated in a currency other than the functional currency of the entity involved are included in foreign exchange (gain) loss, net in the Condensed Consolidated Statements of Operations and Comprehensive Income (Loss).

Cash, cash equivalents, and restricted cash

Cash equivalents include money market accounts and other highly liquid investments with an original maturity date of three months or less at the time of purchase. Cash amounts with restrictions are classified as restricted cash within the Condensed Consolidated Balance Sheets.

Accounts receivable, net

Accounts receivable are carried at the original invoiced amount less an allowance for credit losses. The allowance is estimated by pooling accounts receivables based on similar risk characteristics, and expected credit loss exposure is evaluated for each accounts receivable pool. Invoices are typically issued with net 30-days to net 90-days terms. Account balances are considered delinquent if payment is not received by the due date, and the receivables are written off when deemed uncollectible. These costs are recorded in general and administrative expenses within the Condensed Consolidated Statements of Operations and Comprehensive Income (Loss).

Stock-based compensation

Stock-based compensation is measured at the grant date based on the fair value of the award and is recognized as expense over the requisite service period, which is generally the vesting period. The Company accounts for forfeitures as they occur. The Company used the following assumptions in valuing its market stock units ("MSUs"), shares granted under the Company's 2021 Employee Stock Purchase Program ("ESPP"), time-based service options, which vest over a period of time subject to continued employment ("Time-Based Options"), and return-target options ("Return-Target Options"), which vest upon a realized cash return of the equity investment of funds affiliated with Vista Equity Partners ("Vista"), the Company’s largest shareholder.

Expected term — For time-based awards, the estimated expected term of options granted is generally calculated as the vesting period plus the midpoint of the remaining contractual term, as the Company does not have sufficient historical information to develop reasonable expectations surrounding future exercise patterns and post-vesting employment termination behavior. For awards subject to market and performance conditions, the expected term represents the period of time that the options granted are expected to be outstanding.

Expected volatility — Volatility is estimated based upon observed option-implied volatilities for the Company in addition to a group of peer companies. The Company believes this is the best estimate of the expected volatility over the weighted-average expected term of its option grants.

Risk-free interest rate — The risk-free interest rate is based on the implied yield currently available on U.S. Treasury instruments with terms approximately equal to the expected term of the option.

Expected dividend — The expected dividend assumption was based on the Company’s history and expectation of dividend payouts. The Company currently has no history or expectation of paying cash dividends on its common stock.

Fair value — Following the pricing of the Initial Public Offering, the Company’s shares have traded publicly, and accordingly the Company uses the applicable closing price of its common stock to determine fair value.

Accounting pronouncements not yet adopted

(h) Accounting pronouncements not yet adopted

On November 27, 2023, the FASB issued ASU 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures," which requires incremental disclosures related to an entity's reportable segments. This ASU is effective for annual periods beginning after December 15, 2023. The Company does not expect the adoption of ASU 2023-07 to have a material impact on its consolidated financial statements.

On December 14, 2023, the FASB issued ASU 2023-09, "Income Taxes (Topic 740): Improvements to Income Tax Disclosures," which requires companies to disclose more detailed information in their reconciliation of their statutory tax rate to their effective tax rate. The ASU also requires entities to disclosure more detailed information about income taxes paid, including by jurisdiction, pretax income (or loss) from continuing operations and income tax expense (or benefit). This ASU is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2024. The Company is currently evaluating the impact of the adoption of ASU No. 2023-09 on its consolidated financial statements.

In March 2024, the Securities and Exchange Commission issued Final Rule No. 33-11275, "The Enhancement and Standardization of Climate-Related Disclosures for Investors," that would require registrants to disclose climate-related information in registration statements and annual reports on Form 10-K. In April 2024, given pending legal challenges, the Securities and Exchange Commission issued an order to voluntarily stay the new rules. The Company is currently evaluating the potential impact of the rule on its consolidated financial statements.