Reclassification out of AOCI (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Gains/(losses) on foreign currency translation adjustments
Liquidation of foreign subsidiary			$ 0.1	$ (4.4)
Total gains/(losses) on foreign translation adjustments			0.1	$ (4.4)
Gains/(losses) on available for sale securities:
Gains on available for sale securities	$ 0.6		0.8
Pension and Other Post-Retirement Benefits, net of tax:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	(3.4)	$ (1.8)	(10.3)	$ (5.5)
Amortization of actuarial losses and prior service costs included in net income - Tax	1.3	0.7	3.9	3.0
Amortization of actuarial losses and prior service costs included in net income - Net of Tax	(2.1)	(1.1)	(6.4)	(2.5)
Income Loss Attributable to Reclassification Out Of AOCI Net Of Tax	(1.5)	(1.1)	(5.5)	(6.9)
Selling, General and Administrative Expenses [Member]
Pension and Other Post-Retirement Benefits, net of tax:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	(1.3)	(0.7)	(3.9)	(1.9)
Operating Expense [Member]
Pension and Other Post-Retirement Benefits, net of tax:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	$ (2.1)	$ (1.1)	(6.4)	(3.6)
Other Nonoperating Income (Expense) [Member]
Gains/(losses) on foreign currency translation adjustments
Liquidation of foreign subsidiary			0.1
Icra Gain [Member]
Gains/(losses) on foreign currency translation adjustments
Foreign currency translation adjustment reclassification of losses to net income pursuant to ICRA Step Acquisition				$ (4.4)
Other Income [Member]
Gains/(losses) on available for sale securities:
Gains on available for sale securities	$ 0.6		$ 0.8