Summary of Estimated Amount Amortized from Accumulated Other Comprehensive Income Loss into Net Periodic Pension Cost (Detail) (Pension Benefits, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	$ 11.3
Net prior service cost	0.1
Defined Benefit Plan Future Amortization Of Total Actuarial Gain (Loss), Total	$ 11.4