Nature of Operations	3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]
Nature of Operations	Note 1—Nature of Operations The Trade Desk, Inc. (the “Company”) was formed in November 2009 as a Delaware corporation. The Company is headquartered in Ventura, California and has offices in various cities in North America, Europe, Asia and Australia. The Company is a technology company that empowers buyers of advertising by providing a self-service cloud-based platform on which ad buyers can create, manage, and optimize more expressive data-driven digital advertising campaigns across ad formats, including display, video, audio, native and, social, on a multitude of devices, such as computers, mobile devices, and connected TV.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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