Capital Structure - Secondary Offerings (Details) - Class A	1 Months Ended
	May 31, 2018 $ / shares shares
Class of Stock [Line Items]
Number of shares issued	17,250,000
Purchase price per share (in dollars per share) | $ / shares	$ 27.16
Offering price per share (in dollars per share) | $ / shares	$ 28.00
Number of shares of stock issued	10,518,750
Selling Stockholders
Class of Stock [Line Items]
Number of shares of stock issued	6,731,250
Number of shares issued upon exercise of stock options	2,081,250