Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	May 06, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Carrying value of the notes		$ 4,091.3		$ 4,091.3		$ 4,085.3
Hypothetical annual interest expense				18.4
Hypothetical increase to interest rate swap fair value		3.2		$ 3.2
Interest Rate Swap [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Hypothetical interest rate increase				100.00%
Change in fair value of interest rate swap		0.8	$ 1.0	$ 1.5	$ 0.6
Term Loan Facility due 2021 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Carrying value of the notes		1,820.3		$ 1,820.3		1,818.4
Hypothetical interest rate increase				1.00%
Term Loan Facility due 2021 [Member] | LIBOR
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Floor rate				1.00%
Spread on interest rate	2.75%			2.75%
Notes [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Carrying value of the notes		2,320.9		$ 2,320.9		2,320.7
Fair value of the notes		$ 2,425.5		$ 2,425.5		$ 2,338.1