Supplemental Disclosures of Cash Flow Information - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
AMT credit and other U.S. federal refunds	$ (28.5)	$ (20.0)	$ (63.6)
Tax-payment deferrals	20.0
Tax returns	$ 106.0
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	$ 65.7	63.6	59.4
Employer match on eligible compensation	5.00%
Increased net cash provided by operating activities		54.6	71.9
Increased net cash used by investing activities		$ 54.6	$ 71.9

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

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- Definition

Increased net cash provided by operating activities.

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Increased net cash used by investing activities.

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Matching contributions vesting schedule.

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- Definition

Amount, before allocation of valuation allowances, of deferred tax asset attributable to deductible differences from reserves and accruals, compensation and benefit costs, and other provisions, reserves, and allowances.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated returns and sales allowances.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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- Definition

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

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