Employee Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 30, 2015	Apr. 30, 2014
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 6.0	$ 4.6
Interest Cost	7.7	7.1
Expected Return on Plan Assets	(6.1)	(5.9)
Amortization of Prior Service Cost (Credit)	0	0.1
Amortization of net loss	7.4	3.4
Net Periodic Benefit Cost	15.0	9.3
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	1.1	0.6
Interest Cost	0.8	0.7
Expected Return on Plan Assets	0	0
Amortization of Prior Service Cost (Credit)	(0.2)	(0.2)
Amortization of net loss	0.4	0
Net Periodic Benefit Cost	$ 2.1	$ 1.1