Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ materially from these estimates. For the three months ended March 31, 2020, the impact of the decline in business activity brought about by the Coronavirus pandemic (“COVID-19”) continues to evolve. As a result, many of our estimates and assumptions required increased judgment and carry a higher degree of variability and volatility. As events continue to evolve and additional information becomes available, our estimates may change materially in future periods.
Adoption of New Accounting Standard	Adoption of New Accounting Standard In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASC 326, which requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. As a result, the Company revised its impairment model to utilize an expected loss methodology in place of an incurred loss methodology related to its marketable securities and allowance for doubtful accounts. The Company adopted ASC 326 on January 1, 2020, using a modified retrospective transition method, which requires a cumulative-effect adjustment, if any, to the opening balance of retained earnings to be recognized on the date of adoption with prior periods not restated. The cumulative-effect adjustment recorded on January 1, 2020, is not material.
Accounts Receivable and Allowance for Credit Losses (formerly Allowance for Doubtful Accounts)	Accounts Receivable and Allowance for Credit Losses (formerly Allowance for Doubtful Accounts) Accounts receivable are recorded at the invoiced amount, are unsecured and do not bear interest. The Company performs ongoing credit evaluations of its clients and certain advertisers when the Company’s agreements with its clients contain sequential liability terms that provide that the client payments are not due to the Company until the client has received payment from its clients who are advertisers. We maintain an allowance for credit losses for expected uncollectible accounts receivable, which is recorded as an offset to accounts receivable and changes in such are classified as general and administrative expense in the Consolidated Statements of Income. Based on the implementation of CECL during the first quarter of 2020, the Company considers macro-economic factors and industry specific default rates in the valuation of trade receivables and the related allowance for credit losses. The industry specific default rates are applied to the advertiser’s industry in the case where the receivables are subject to sequential liability or the Company is engaged with the advertiser directly. The services of an outside valuation firm were used to assist in the determination of the macro-economic factors and the industry default rates. For the three months ended March 31, 2020, our assessment considered business and market disruptions caused by COVID-19 and estimates of credit defaults by industry.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes. This guidance will be effective for the Company in the first quarter of 2021 on a prospective basis, and early adoption is permitted. The Company is currently evaluating the impact of the new guidance on our consolidated financial statements. In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848) (“ASU 2020-04”), which provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships, and other transactions affected by the discontinuation of the London Interbank Offered Rate or by another reference rate expected to be discontinued. The amendments are effective for all entities as of March 12, 2020 through December 31, 2022. The Company is currently evaluating the impacts of the provisions of ASU 2020-04 on our financial condition, results of operations, and cash flows.

Basis of Presentation and Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2020

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ materially from these estimates.

For the three months ended March 31, 2020, the impact of the decline in business activity brought about by the Coronavirus pandemic (“COVID-19”) continues to evolve. As a result, many of our estimates and assumptions required increased judgment and carry a higher degree of variability and volatility. As events continue to evolve and additional information becomes available, our estimates may change materially in future periods.

Adoption of New Accounting Standard

In June 2016, the Financial Accounting Standards Board (“FASB”) issued ASC 326, which requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. As a result, the Company revised its impairment model to utilize an expected loss methodology in place of an incurred loss methodology related to its marketable securities and allowance for doubtful accounts. The Company adopted ASC 326 on January 1, 2020, using a modified retrospective transition method, which requires a cumulative-effect adjustment, if any, to the opening balance of retained earnings to be recognized on the date of adoption with prior periods not restated. The cumulative-effect adjustment recorded on January 1, 2020, is not material.

Accounts Receivable and Allowance for Credit Losses (formerly Allowance for Doubtful Accounts)

Accounts receivable are recorded at the invoiced amount, are unsecured and do not bear interest. The Company performs ongoing credit evaluations of its clients and certain advertisers when the Company’s agreements with its clients contain sequential liability terms that provide that the client payments are not due to the Company until the client has received payment from its clients who are advertisers. We maintain an allowance for credit losses for expected uncollectible accounts receivable, which is recorded as an offset to accounts receivable and changes in such are classified as general and administrative expense in the Consolidated Statements of Income. Based on the implementation of CECL during the first quarter of 2020, the Company considers macro-economic factors and industry

specific default rates in the valuation of trade receivables and the related allowance for credit losses. The industry specific default rates are applied to the advertiser’s industry in the case where the receivables are subject to sequential liability or the Company is engaged with the advertiser directly. The services of an outside valuation firm were used to assist in the determination of the macro-economic factors and the industry default rates. For the three months ended March 31, 2020, our assessment considered business and market disruptions caused by COVID-19 and estimates of credit defaults by industry.

Recent Accounting Pronouncements

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes. This guidance will be effective for the Company in the first quarter of 2021 on a prospective basis, and early adoption is permitted. The Company is currently evaluating the impact of the new guidance on our consolidated financial statements.

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848) (“ASU 2020-04”), which provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships, and other transactions affected by the discontinuation of the London Interbank Offered Rate or by another reference rate expected to be discontinued. The amendments are effective for all entities as of March 12, 2020 through December 31, 2022. The Company is currently evaluating the impacts of the provisions of ASU 2020-04 on our financial condition, results of operations, and cash flows.