Financial Data by Segment - Schedule of Revenues and Assets by Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 1,345.7	$ 1,008.9	$ 892.6	$ 895.3	$ 974.5	$ 688.8	$ 638.9	$ 594.7	$ 4,142.6	$ 2,897.0	$ 2,694.2
Assets	3,149.8				2,872.7				3,149.8	2,872.7	2,364.8
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									3,771.9	2,582.1	2,368.6
Assets	2,579.1				2,424.9				2,579.1	2,424.9	1,943.7
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									251.4	213.7	224.5
Assets	237.9				171.6				237.9	171.6	174.5
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									92.1	78.3	69.8
Assets	238.1				202.5				238.1	202.5	163.2
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									27.3	23.0	31.3
Assets	$ 94.7				$ 73.7				$ 94.7	$ 73.7	$ 83.3