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Supplemental Disclosures of Cash Flow Information - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
AMT credit and other U.S. federal refunds			$ (28.5)
Tax-payment deferrals			20.0
Tax returns			106.0
Net operating losses in U.K. additional cash tax payments		$ 49.0	$ 28.4
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%	5.00%	5.00%
Matching contributions vesting schedule	5 years
Contribution expense to plan	$ 86.0	$ 73.8	$ 65.7
Employer match on eligible compensation	5.00%	5.00%

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Defined benefit plan percentage of eligible compensation for matching contributions by employer.

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The amount of cash received during the period as refunds for the overpayment of taxes.

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