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Retirement Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Expected period of return on plan assets, years	10 years	10 years
Minimum contribution by employer	$ 0.0	$ 0.0	$ 0.0
Discretionary contributions by employer	0.0	30.0	0.0
Fair value of plan assets	243.7	220.0	219.4
Postretirement benefit obligation and unfunded status of plan	274.4	253.2	271.4
Net periodic postretirement benefit cost	$ 3.6	(1.0)	2.7
Foreign Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	$ 39.8	34.9	32.0
Matching contributions by employer, percentage	100.00%
Additional percentage of eligible compensation for matching contributions by employer	5.00%
Qualified Contributory Savings and Thrift 401(k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	$ 59.4	53.9	51.6
Matching contributions by employer, percentage	100.00%
Matching contributions vesting schedule	5 years
Nonqualified Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	$ 7.1	6.5	6.4
Fair value of plan assets	452.9	355.0
Retiree Health Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Postretirement benefit obligation and unfunded status of plan	1.7	2.0
Net periodic postretirement benefit cost	$ 0.4	$ 0.3	$ 0.3

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