Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Assets [Abstract]
Trading securities	$ 2.6	$ 2.3
Derivative financial instruments	0.2
Total assets	2.8	2.3
Liabilities [Abstract]
Derivative financial instruments	0.6	1.4
Deferred compensation obligations	2.6	2.3
Total liabilities	3.2	3.7
Level 1 [Member]
Assets [Abstract]
Trading securities	2.6	2.3
Derivative financial instruments	0
Total assets	2.6	2.3
Liabilities [Abstract]
Derivative financial instruments	0	0
Deferred compensation obligations	2.6	2.3
Total liabilities	2.6	2.3
Level 2 [Member]
Assets [Abstract]
Trading securities	0	0
Derivative financial instruments	0.2
Total assets	0.2	0
Liabilities [Abstract]
Derivative financial instruments	0.6	1.4
Deferred compensation obligations	0	0
Total liabilities	0.6	1.4
Level 3 [Member]
Assets [Abstract]
Trading securities	0	0
Derivative financial instruments	0
Total assets	0	0
Liabilities [Abstract]
Derivative financial instruments	0	0
Deferred compensation obligations	0	0
Total liabilities	$ 0	$ 0