Restructuring - Costs Included in Selling, General & Administrative expenses on Consolidated Statements of Income (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 7.4	$ 14.1	$ 14.0
Transformation costs	[1]	11.7	0.0	0.0
Total restructuring and transformation costs		19.1	14.1	14.0
Severance and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs		7.0	9.7	11.7
Transformation Program
Restructuring Cost and Reserve [Line Items]
Restructuring costs	[2]	$ 0.4	$ 4.4	$ 2.3

[1] Transformation costs primarily consist of professional services and project management and related costs.

[2] Other restructuring costs primarily consist of asset impairment and various contract termination costs.