Equity - Summary of Dividends Paid and Stock Repurchases and Reitrements (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions			3 Months Ended			9 Months Ended
	Mar. 22, 2019	Jan. 29, 2019	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Sep. 30, 2018
Dividends
Per share (in dollars per share)	$ 0.19		$ 0.19		$ 0.18
Per share, declared (in dollars per share)		$ 0.19	$ 0.19		$ 0.18
Amount			$ 66.2		$ 62.1
Stock repurchases
Amount			2.9		604.2
Repurchase and retirement of common stock			$ 2.9		$ 754.2
Stock Repurchase Program 2018
Stock repurchases
Shares (in shares)			0.0		23.3
Average price per share (in dollars per share)			$ 0.00		$ 25.80
Amount			$ 0.0		$ 750.0
Shares received (in shares)			0.0		23.3
Accelerated Share Repurchase Program
Stock repurchases
Shares (in shares)			29.3	6.0	23.3
Average price per share (in dollars per share)			$ 25.62
Repurchase and retirement of common stock						$ 750.0
Shares received (in shares)			29.3	6.0	23.3