Retirement Plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
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
Discretionary contributions by employer	0	30,000,000.0	0
Fair value of plan assets	$ 262,800,000	243,700,000	220,000,000.0
Foreign Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching contributions by employer, percentage	100.00%
Percentage of eligible compensation for matching contributions by employer	5.00%
Contribution expense to plan	$ 44,300,000	39,800,000	34,900,000
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]
Matching contributions by employer, percentage	100.00%
Percentage of eligible compensation for matching contributions by employer	5.00%
Matching contributions vesting schedule	5 years
Contribution expense to plan	$ 63,600,000	59,400,000	53,900,000
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	$ 7,800,000	7,100,000	$ 6,500,000
Fair value of plan assets	$ 497,300,000	$ 452,900,000