Market price premium percentage.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of noncash expense for share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Earnings Per Share Data ("EPS") and Stock Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anti-dilutive weighted average stock options excluded from computation of earnings per share	4,100,000	7,100,000	4,300,000	6,700,000
Unrecognized compensation cost related to unvested options and restricted stock	$ 144,600		$ 144,600
Stock options granted during period			2,396,402
Market price premium percentage			10.00%
Weighted-average grant date fair value, per option			$ 39.66
Compensation cost recognized			$ 55,548	$ 49,928
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	14,600	$ 13,000	44,800	41,600
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	$ 3,500	$ 2,500	$ 9,600	$ 7,300
Unrecognized compensation cost vesting period			2 years 9 months 18 days
Restricted shares and restricted units granted during period			150,860
Weighted-average grant date fair value, per share			$ 138.80
Unvested Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost vesting period			2 years 9 months 18 days
Market Price Premium
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted during period			406,952