The Company	9 Months Ended
Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
The Company	1. THE COMPANY Organization and Description of Business Roku, Inc. (the “Company” or “Roku”), was formed in October 2002 as Roku LLC under the laws of the State of Delaware. On February 1, 2008, Roku LLC was converted into Roku, Inc., a Delaware corporation. The Company’s TV streaming platform allows users to easily discover and access a wide variety of movies and TV episodes, as well as live sports, music, news and more. The Company operates in two reportable segments and generates revenue through the sale of streaming players, advertising, subscription and transaction revenue sharing, as well as through licensing arrangements with TV brands and cable, satellite, and telecommunication service operators (“service operators”). Initial Public Offering On October 2, 2017, the Company completed its initial public offering (“IPO”) of Class A common stock, in which it sold 10.4 million shares, including 1.4 million shares pursuant to the underwriters’ over-allotment option. The shares were sold at an IPO price of $14.00 per share for net proceeds of $134.8 million, after deducting underwriting discounts and commissions of $10.1 million. Upon the closing of the Company’s IPO, all outstanding shares of its convertible preferred stock automatically converted into 80.8 million shares of Class B common stock and all outstanding convertible preferred stock warrants automatically converted to Class B common stock warrants on a one-for-one basis. The Company has two classes of authorized common stock – Class A common stock and Class B common stock. Class A common stock entitles holders to one vote per share, and Class B common stock entitles holders to 10 votes per share.

1. THE COMPANY

Organization and Description of Business

Roku, Inc. (the “Company” or “Roku”), was formed in October 2002 as Roku LLC under the laws of the State of Delaware. On February 1, 2008, Roku LLC was converted into Roku, Inc., a Delaware corporation. The Company’s TV streaming platform allows users to easily discover and access a wide variety of movies and TV episodes, as well as live sports, music, news and more. The Company operates in two reportable segments and generates revenue through the sale of streaming players, advertising, subscription and transaction revenue sharing, as well as through licensing arrangements with TV brands and cable, satellite, and telecommunication service operators (“service operators”).

Initial Public Offering

On October 2, 2017, the Company completed its initial public offering (“IPO”) of Class A common stock, in which it sold 10.4 million shares, including 1.4 million shares pursuant to the underwriters’ over-allotment option. The shares were sold at an IPO price of $14.00 per share for net proceeds of $134.8 million, after deducting underwriting discounts and commissions of $10.1 million. Upon the closing of the Company’s IPO, all outstanding shares of its convertible preferred stock automatically converted into 80.8 million shares of Class B common stock and all outstanding convertible preferred stock warrants automatically converted to Class B common stock warrants on a one-for-one basis. The Company has two classes of authorized common stock – Class A common stock and Class B common stock. Class A common stock entitles holders to one vote per share, and Class B common stock entitles holders to 10 votes per share.