Share based compensation arrangement by share based payment award equity instruments other than options earned.

No definition available.

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- Definition

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.

+ References

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

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.

+ References

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

+ References

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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).

+ References

+ Details

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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.

+ References

No definition available.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB
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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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- Definition

Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

+ References

No definition available.

+ Details

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- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

+ References

No definition available.

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Share-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	May 31, 2018	Dec. 31, 2015	May 31, 2011
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	1,040,000	1,807,000	1,077,000
Stock options outstanding	5,746,000	6,356,000	6,112,000		5,507,000
Number of common stock available for future grant	6,800,000
Weighted-average fair values of stock options granted	$ 43.42	$ 25.11	$ 21.49
Weighted average remaining contractual term for stock options outstanding	6 years 8 months 12 days
Share-based compensation expense	$ 58,068,000	$ 42,522,000	$ 28,464,000
Number of stock options exercisable	3,900,000
Stock options exercisable, weighted average exercise price	$ 31.07
Stock options exercisable, weighted-average remaining contractual term	5 years 10 months 24 days
Stock options exercised in period intrinsic value	$ 117,000,000	61,400,000	13,200,000
Stock options intrinsic value of options outstanding	186,300,000
Stock options intrinsic value of options exercisable	158,200,000
Cash received from stock option exercises	$ 29,500,000	$ 13,900,000	$ 2,400,000
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, term	3 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, term	4 years
Share-based compensation, contractual term	10 years
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted	540,000	588,000	326,000
Share-based compensation expense	$ 21,900,000	$ 13,900,000	$ 8,300,000
Unrecognized compensation cost	$ 51,600,000
Stock vesting period	2 years 3 months 18 days
Total intrinsic value vested in period	$ 35,500,000	14,900,000	12,200,000
Intrinsic value outstanding	$ 80,900,000
Restricted Stock Units (RSUs) \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	4 years
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 35,400,000	$ 28,200,000	$ 18,400,000
Unrecognized compensation cost	$ 55,400,000
Stock vesting period	2 years 3 months 18 days
Stock Options \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	3 years
Share-based compensation, term	7 years
Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	4 years
Share-based compensation, term	10 years
Performance-based RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted	200,000	0	200,000
Share-based compensation expense	$ 0	$ 400,000	$ 1,800,000
Unrecognized compensation cost	19,700,000
Intrinsic value outstanding	$ 23,600,000
Performance restricted stock units earned during period	0	200,000	0
Performance-based RSUs \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	4 years
Performance-based RSUs \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	5 years
Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	70,000	410,000	0
Stock vesting period	4 years	4 years
Stock options outstanding	245,162
Employees \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units granted	20,000	12,500	0
RSUs outstanding	245,162
Employees \| Restricted Stock Units (RSUs) \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	3 years	3 years
Employees \| Restricted Stock Units (RSUs) \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period	4 years	4 years
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock authorized for issuance	300,000			300,000
Number of shares purchased	0
Share-based compensation expense	$ 800,000
ESPP \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Discounted purchase price percentage of common stock authorized for issuance	85.00%
2011 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock authorized for issuance						19,000,000
Share Based Compensation Arrangement Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock authorized for issuance	7,200,000
PRSUs Converted into Common Shares \| Performance-based RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value outstanding		$ 8,800,000