Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 996.0	$ 889.0	$ 951.9
Ending balance	1,097.5	996.0	889.0
Minimum Pension/Post Retirement Liability Adjustments
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(18.8)	(24.1)	(11.3)
Current-year adjustments, pre-tax	(0.5)	8.6	(20.8)
Tax benefit (expense)	(0.3)	(3.3)	8.0
Other comprehensive loss	(0.8)	5.3	(12.8)
Reclassification to retained earnings	(4.2)
Ending balance	(23.8)	(18.8)	(24.1)
Foreign Currency Translation
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	0.0	0.0	0.0
Current-year adjustments, pre-tax	(12.9)	0.0	0.0
Tax benefit (expense)	0.0	0.0	0.0
Other comprehensive loss	(12.9)	0.0	0.0
Reclassification to retained earnings	0.0
Ending balance	(12.9)	0.0	0.0
Interest Rate Swaps
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(0.2)	(4.4)	(1.3)
Current-year adjustments, pre-tax	0.4	6.8	(5.0)
Tax benefit (expense)	(0.4)	(2.6)	1.9
Other comprehensive loss	0.0	4.2	(3.1)
Reclassification to retained earnings	0.2
Ending balance	0.0	(0.2)	(4.4)
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(19.0)	(28.5)	(12.6)
Current-year adjustments, pre-tax	(13.0)	15.4	(25.8)
Tax benefit (expense)	(0.7)	(5.9)	9.9
Other comprehensive loss	(13.7)	9.5	(15.9)
Reclassification to retained earnings	(4.0)
Ending balance	$ (36.7)	$ (19.0)	$ (28.5)

Increase (Decrease) in Accumulated Other Comprehensive Income (Loss)

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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