CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Pension and post-retirement benefits, tax expense (benefit)	$ 52.8	$ 12.0	$ (22.1)
Net gain (loss) on derivative instruments, tax expense (benefit)	(4.0)	21.7	(29.5)
Unrealized gain (loss) on marketable securities, tax expense	$ 0.0	$ 0.0	$ 0.0