Components Of Net Periodic Benefit Cost (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Costs
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1.1	$ 0.9	$ 0.9
Interest cost	4.0	4.2	4.6
Expected return on plan assets	(4.2)	(3.9)	(4.3)
Amortization of prior service cost	0	0	0
Settlements/curtailments	0	0	0
Recognized actuarial loss (gain)	0.9	0.2	0
Net periodic benefit cost	1.8	1.4	1.2
Nonpension Postretirement Costs
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.4	0.4	0.4
Interest cost	1.1	1.2	1.3
Expected return on plan assets	0	0	0
Amortization of prior service cost	(0.8)	(0.1)	0.1
Settlements/curtailments	(0.3)	0	0
Recognized actuarial loss (gain)	0.1	0.2	0
Net periodic benefit cost	$ 0.5	$ 1.7	$ 1.8