Capital Stock - Narratives (Details) - USD ($)		12 Months Ended
	Feb. 01, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 04, 2019	Apr. 30, 2018	Jan. 31, 2017	Jan. 03, 2017
Class of Stock
Common stock authorized (shares)	900,000,000	900,000,000	900,000,000					904,732,200
Common stock, par value (usd per share)	$ 0.01	$ 0.01	$ 0.01					$ 0.01
Preferred stock, shares authorized (shares)	90,000,000	90,000,000	90,000,000				8,750,000
Preferred stock, par value (usd per share)	$ 0.01	$ 0.01	$ 0.01				$ 0.01
Shares held in employee trust (shares)		193,941	193,941
Shares held in employee trust		$ 12,400,000	$ 12,400,000
Proceeds from sale of common stock, net of underwriting fees and commissions	$ 480,300,000	0	$ 0	$ 480,306,000
Costs associated with initial public offering	7,900,000
Deferred offering costs	$ 5,900,000
Share repurchase program authorized						$ 250,000,000.0
Shares remaining for repurchase, value		$ 175,000,000.0			$ 175,000,000.0
Common Class A
Class of Stock
Common stock authorized (shares)	900,000,000							900,000,000
Common stock, par value (usd per share)	$ 0.01
Class B-1 Common Stock
Class of Stock
Common stock authorized (shares)								4,732,200
Common stock
Class of Stock
Conversion of stock (shares)	309,404
Common stock
Class of Stock
Common shares repurchased (shares)		1,192,419	5,287,964
Shares repurchased		$ 20,000,000.0	$ 125,000,000.0
Common stock | Common Class A
Class of Stock
Common shares repurchased (shares)				2,266
Shares repurchased		$ 12,000	$ 53,000
Common stock | Class B-1 Common Stock
Class of Stock
Conversion of stock (shares)				(177,221)