Retirement Plans - Amounts Recognized in Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Total	$ (60.2)	$ 390.9	$ (919.0)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Amortization of Net actuarial loss	40.5
Amortization of Net prior service credit	0.0
Amounts arising during the period, Net actuarial loss	7.9
Amounts arising during the period, Divestiture	3.8
Amounts arising during the period, Net prior service credit	0.0
Amounts arising during the period, Settlements	0.2
Amounts arising during the period, Foreign currency loss	2.5
Total	54.9
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Amortization of Net actuarial loss	0.0
Amortization of Net prior service credit	(26.9)
Amounts arising during the period, Net actuarial loss	32.0
Amounts arising during the period, Divestiture	0.0
Amounts arising during the period, Net prior service credit	0.1
Amounts arising during the period, Settlements	0.0
Amounts arising during the period, Foreign currency loss	0.1
Total	$ 5.3