Stockholders' Equity - Additional Information (Details) - $ / shares		6 Months Ended
	Jun. 15, 2018	Jul. 31, 2018	Jun. 14, 2018	Jan. 31, 2018
Class Of Stock [Line Items]
Common Stock, conversion features		On June 14, 2018, all of our outstanding shares of Class B common stock automatically converted into the same number of shares of Class A common stock pursuant to the terms of our Amended and Restated Certificate of Incorporation. No additional shares of Class B common stock will be issued following such conversion. The conversion occurred pursuant to Article IV of the Amended and Restated Certificate of Incorporation, which provided that each one share of Class B common stock would convert automatically, without any further action, into one share of Class A common stock on the first trading day falling on or after the date on which the outstanding shares of Class B common stock represent less than 5% of the aggregate number of shares of the then outstanding Class A common stock and Class B common stock.
Preferred stock, shares authorized		100,000,000		100,000,000
Preferred stock, par value		$ 0.0001		$ 0.0001
Preferred stock, shares issued		0		0
Preferred stock, shares outstanding		0		0
Class B Common Stock
Class Of Stock [Line Items]
Maximum percentage of outstanding shares of Class A and Class B common stock, for automatic conversion of shares of Class B common stock			5.00%
Additional common shares issued			0
Reduction in number of authorized shares of common stock	200,000,000
Common Stock, shares authorized				200,000,000
Common Stock, par value				$ 0.0001
Common Stock, shares issued				11,383,525
Common Stock, shares outstanding				11,383,525
Class A Common Stock
Class Of Stock [Line Items]
Common Stock, shares authorized		1,000,000,000		1,000,000,000
Common Stock, par value		$ 0.0001		$ 0.0001
Common Stock, shares issued		141,605,601		125,933,323
Common Stock, shares outstanding		141,605,601		125,933,323