Stockholders' Equity - At-the-Market Offerings - Additional Information (Details) - At-the-Market Offerings - Class A Common Stock - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 12, 2019
Class Of Stock [Line Items]
Maximum aggregate offering price of common stock		$ 100.0
Gross proceeds from issuance of common stock	$ 100.0
Number of shares Issued	1.4
Average selling price per share	$ 72.00
Stock Issuance Costs	$ 2.0