Earnings Per Share Data ("EPS") and Stock Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anti-dilutive weighted average stock options excluded from computation of earnings per share	7,000,000	2,900,000
Stock options granted during period	2,390,390
Weighted-average grant date fair value, per share	$ 30.43
Compensation cost recognized	$ 17,591,000	$ 19,700,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	15,800,000	18,900,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized, pre-tax charge	1,500,000	$ 545,000
Unrecognized compensation cost	$ 175,700,000
Unrecognized compensation cost vesting period	3 years 1 month 6 days
Restricted shares granted during period	142,288,000
Weighted-average grant date fair value, per share	$ 134.23
Unvested Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 175,700,000
Unrecognized compensation cost vesting period	3 years 1 month 6 days

Share based compensation arrangement by share based payment award compensation cost before tax

No definition available.

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- Definition

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.

+ References

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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- Definition

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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- Definition

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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- 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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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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