Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		$ 1,675.1
Other comprehensive income (loss) before reclassifications		6.0	$ (14.3)
Tax (provision) benefit	[1]	1.6	5.5
Other comprehensive income (loss) before reclassifications, net of taxes		7.6	(8.8)
Reclassifications		7.6	3.2
Tax provision (benefit)		(1.8)	(0.3)
Reclassifications, net of tax		5.8	2.9
Other comprehensive income (loss)		13.4	(5.9)
Ending balance		1,671.8
Derivative Instruments Designated as Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(9.9)	(8.7)
Other comprehensive income (loss) before reclassifications		1.4	(15.9)
Tax (provision) benefit	[1]	1.6	5.5
Other comprehensive income (loss) before reclassifications, net of taxes		3.0	(10.4)
Reclassifications	[2]	4.3	0.6
Tax provision (benefit)		(0.7)	0.6
Reclassifications, net of tax		3.6	1.2
Other comprehensive income (loss)		6.6	(9.2)
Ending balance		(3.3)	(17.9)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(116.0)	(94.2)
Other comprehensive income (loss) before reclassifications		4.6	1.6
Tax (provision) benefit	[1]	0.0	0.0
Other comprehensive income (loss) before reclassifications, net of taxes		4.6	1.6
Reclassifications		0.0	0.0
Tax provision (benefit)		0.0	0.0
Reclassifications, net of tax		0.0	0.0
Other comprehensive income (loss)		4.6	1.6
Ending balance		(111.4)	(92.6)
Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(109.6)	(105.1)
Other comprehensive income (loss) before reclassifications		0.0	0.0
Tax (provision) benefit	[1]	0.0	0.0
Other comprehensive income (loss) before reclassifications, net of taxes		0.0	0.0
Reclassifications	[3]	3.3	2.6
Tax provision (benefit)		(1.1)	(0.9)
Reclassifications, net of tax		2.2	1.7
Other comprehensive income (loss)		2.2	1.7
Ending balance		(107.4)	(103.4)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(235.5)	(208.0)
Ending balance		$ (222.1)	$ (213.9)

[1] Income taxes are not provided for foreign currency translation adjustment.

[2] See Note 5 of the notes to condensed consolidated financial statements.

[3] These components are included in the computation of net periodic pension cost. See Note 9 of the notes to condensed consolidated financial statements.