Organization and Basis of Presentation - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income
Net income	$ 357.6	$ 160.7	$ 524.9	$ 300.2
Less: Net income attributable to noncontrolling interests	2.6	2.4	7.6	10.2
NET INCOME	355.0	158.3	517.3	290.0
Less: net income allocated to RSUs	0.2	0.3	0.4	0.5
Net income allocated to common stock	$ 354.8	$ 158.0	$ 516.9	$ 289.5
Common Shares Outstanding
Weighted average equivalent common shares outstanding - basic (in shares)	268.6	142.5	197.9	142.5
Add: effect of dilutive securities (in shares)	0.2	0.0	0.1	0.0
Weighted average equivalent common shares outstanding - diluted (in shares)	268.8	142.5	198.0	142.5
Basic and Diluted EPS
Basic and Diluted EPS (in dollars per share)	$ 1.32	$ 1.11	$ 2.61	$ 2.03