Retirement Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
U.S. Pension Benefits
Retirement and Postemployment Benefits
Service costs	$ 1.1	$ 1.0
Interest costs	3.6	3.7
Expected return on plan assets	(3.5)	(3.5)
Amortization of unrecognized prior service costs, net	0.2	0.2
Amortization of net loss	1.2	0.9
Net pension costs	2.6	2.3
Non-U.S. pension benefits
Retirement and Postemployment Benefits
Service costs	0.4	0.4
Interest costs	0.8	1.1
Expected return on plan assets	(0.3)	(0.3)
Amortization of unrecognized prior service costs, net	0	0
Amortization of net loss	0	0
Net pension costs	$ 0.9	$ 1.2