Income Taxes - Reconciliation of Tax Provision for Continuing Operations (Detail)	12 Months Ended
	Dec. 31, 2020 Rate	Dec. 31, 2019 Rate	Dec. 31, 2018 Rate
Income Tax Disclosure [Abstract]
Tax provision at U.S. statutory rate	21.00%	21.00%	21.00%
Foreign tax rate differential	1.60%	2.80%	3.70%
Tax on undistributed foreign earnings	7.40%	1.80%	(1.20%)
Audit settlements and unrecognized tax benefits	(5.40%)	0.10%	(0.30%)
Effective Income Tax Reconciliation, Pension settlement AOCI expense	5.90%	0.00%	0.00%
Italy patent box	(5.60%)	(1.20%)	(1.00%)
Excess tax benefits on stock-based compensation	(3.60%)	(1.10%)	(0.60%)
State and local income tax	(2.40%)	0.70%	1.50%
Valuation allowance on deferred tax assets	1.50%	(0.50%)	(2.40%)
U.S. tax on foreign earnings	(0.20%)	0.00%	0.50%
U.S. permanent items	(0.10%)	(1.00%)	0.40%
Tax exempt interest	0.00%	0.00%	(5.80%)
One-time tax on foreign earnings - Tax Act	0.00%	0.00%	(1.00%)
Federal deferred taxes remeasurement - Tax Act	0.00%	0.00%	0.40%
Other adjustments	(2.10%)	(0.90%)	(0.40%)
Effective income tax rate	18.00%	21.70%	14.80%