Subsequent Event	9 Months Ended
Sep. 30, 2019
Subsequent Events [Abstract]
Subsequent Event	15. SUBSEQUENT EVENT On October 22, 2019, the Company announced that it had entered into an agreement and plan of merger to purchase Boston-based dataxu, Inc., a demand-side platform (DSP) company that enables marketers to plan and buy video advertising campaigns, for aggregate consideration of approximately $150.0 million consisting of equal parts cash and shares of the Company’s Class A Common Stock. The acquisition was consummated on November 8, 2019.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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