Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Tax benefits recognized for net operating loss carryforwards	$ 12.4	$ 5.0	$ 4.3
U.S. statutory income tax rate	21.00%	21.00%	35.00%
Deferred tax benefits due to the Tax Act			$ 304.0
Tax expense due to the Tax Act			130.6
Net operating loss carryforwards	$ 460.9
Deferred tax asset related to operating loss carryforwards	123.3
Valuation allowance	$ 118.5	$ 118.3
Carryforward description	The carryforward periods range from four years to indefinite, subject to certain limitations under applicable laws.
Cash paid for income taxes	$ 586.0	607.6	661.4
Unrecognized tax benefits	30.7	21.2	22.9	$ 17.3
Unrecognized tax benefits that, if recognized, would affect the effective tax rate	28.4	18.9	16.8
Expense (income) related to interest	0.8	(0.1)	0.2
Accrued interest expense and penalties	1.9	$ 1.1	$ 1.1
Unrecognized tax benefits resulting from research and development tax credits	$ 7.9
Internal Revenue Service (IRS)
Income Taxes [Line Items]
Tax examinations	the United States Internal Revenue Service has completed examinations of the Company’s tax returns for all years through 2014.
Net Operating Loss Carryforwards
Income Taxes [Line Items]
Valuation allowance	$ 99.6
Minimum
Income Taxes [Line Items]
Operating loss carryforwards periods	4 years
Foreign
Income Taxes [Line Items]
Net operating loss carryforwards	$ 370.7
United States
Income Taxes [Line Items]
Net operating loss carryforwards	$ 90.2
Other Major Jurisdictions | Earliest Tax Year
Income Taxes [Line Items]
Tax year remain subject to examination	2011
Other Major Jurisdictions | Latest Tax Year
Income Taxes [Line Items]
Tax year remain subject to examination	2019