CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Pension and post-retirement benefits, tax	$ (2.6)	$ (1.2)	$ (5.2)	$ (2.4)
Net gain (loss) on derivative instruments, tax	8.1	(4.6)	(3.5)	15.3
Unrealized gain (loss) on marketable securities, tax	$ 0	$ 0	$ 0	$ 0.1