Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Effective tax rate	15.70%	14.40%			17.00%	20.40%
Income tax reconciliation nondeductible expense executive compensation		$ 5.0				$ 5.0
Effective tax rate increased related to limitations on deduction of executive compensation			9.80%	7.50%		3.80%
Amount of gross unrecognized tax benefits excluding interest and penalties	$ 47.5				$ 47.5		$ 43.5
Net unrecognized tax benefit excluding interest and penalties that would impact effective tax rate	39.2				39.2
Accrued interest on unrecognized tax benefits	$ 0.6				0.6		$ 0.5
Net unrecognized tax benefits, excluding interest and penalties, related to foreign tax positions					$ 0.9