Inventories - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2016
Inventory Disclosure [Abstract]
Reduction to net loss resulting from effect of LIFO inventory liquidation	$ 0.0	$ 0.8	$ 1.7