Composition of Domestic Pension Plan Assets (Detail) (Pension Benefits, Domestic, USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 270.0	$ 256.5	$ 234.6
Equity Securities And Funds, Domestic
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	39.2	44.2
Equity Securities And Funds, International
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50.2	48.6
Fixed Income Securities And Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	87.1	76.4
Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	89.6	84.1
Cash And Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3.9	3.2
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	135.0	100.9
Level 1 | Equity Securities And Funds, Domestic
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	39.2	10.5
Level 1 | Fixed Income Securities And Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	66.8	62.4
Level 1 | Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	26.2	26.0
Level 1 | Cash And Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2.8	2.0
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	121.2	141.5
Level 2 | Equity Securities And Funds, Domestic
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		33.7
Level 2 | Equity Securities And Funds, International
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50.2	48.6
Level 2 | Fixed Income Securities And Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20.3	14.0
Level 2 | Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50.7	45.2
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13.8	14.1	13.3
Level 3 | Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12.7	12.9
Level 3 | Cash And Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1.1	$ 1.2