Changes in Accumulated Other Comprehensive Income/(Loss) by Component - Summary of Reclassifications Out of Accumulated Other Comprehensive Income/(Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Pension and Post-retirement liabilities:
Amortization of loss, net of tax	$ 0.1	$ 0.1	$ 0.3	$ 0.2
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Pension and Post-retirement liabilities:
Amortization of loss, net of tax	0.1	0.1	0.3	0.2
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Pension and Post-retirement liabilities:
Amortization of loss reclassified into Selling, general and administrative expenses	0.2	0.1	0.4	0.3
Tax income	(0.1)	(0.1)	(0.2)	(0.1)
Amortization of loss, net of tax	$ 0.1	$ 0.1	$ 0.3	$ 0.2