Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Taxes [Line Items]
Effective income tax rate	27.40%	30.50%
Increase/(decrease) in effective tax rate due to impact of discrete tax items	0.50%	3.30%
Net increase to income tax reserves for unrecognized tax benefits based on tax positions related to current and prior years	$ 1.7
Unrecognized tax benefits reserve that would impact effective tax rate if released into income	56.1
Current Tax Payable Within Other Current Liabilities
Income Taxes [Line Items]
Unrecognized tax benefits reserve that would impact effective tax rate if released into income	5.6
Non-Current Tax Payable Within Other Non-current Liabilities
Income Taxes [Line Items]
Unrecognized tax benefits reserve that would impact effective tax rate if released into income	$ 50.5