Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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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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Unrecognized cost of unvested options awarded to employees as compensation.

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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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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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No definition available.

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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 ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anti-dilutive weighted average stock options excluded from computation of earnings per share	3,000,000	0	4,400,000	2,900,000
Stock options granted during period (net of cancellations)			2,980,725
Weighted-average grant date fair value, per share			$ 27.07
Compensation cost recognized			$ 29,053,000	$ 24,693,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized	$ 13,000,000	$ 10,900,000	27,900,000	23,600,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized	448,000	$ 340,000	$ 599,000	$ 659,000
Unrecognized compensation cost vesting period			3 years
Unvested Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 124,600,000		$ 124,600,000
Unrecognized compensation cost vesting period			3 years