Retirement Benefits - Schedule of Components of Retirement Benefit Expense (Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	May. 31, 2015	May. 31, 2014	May. 31, 2015	May. 31, 2014
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2.7	$ 2.2	$ 5.4	$ 4.4
Interest cost on benefit obligation	15.9	16.7	31.8	33.5
Assumed return on plan assets	(22.1)	(23.2)	(44.2)	(46.4)
Amortization of prior service credits	0.0	0.0	0.0	0.0
Recognized net actuarial losses (gains)	20.9	13.5	41.7	26.9
Retirement benefit expense (income)	17.4	9.2	34.7	18.4
Postretirement Medical and Life Insurance Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0	0.0	0.0
Interest cost on benefit obligation	0.5	0.7	1.0	1.3
Assumed return on plan assets	0.0	0.0	0.0	0.0
Amortization of prior service credits	(0.2)	(0.2)	(0.5)	(0.4)
Recognized net actuarial losses (gains)	(0.9)	(0.8)	(1.8)	(1.5)
Retirement benefit expense (income)	$ (0.6)	$ (0.3)	$ (1.3)	$ (0.6)