Number of shares of common stock outstanding increase percentage.

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Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Equity Incentive Plans

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- Definition

Share-based compensation arrangement by share-based payment award, options, grants in period, vest percentage per annum.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Purchase Offering Period

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Share-based compensation arrangement by share-based payment award, requisite service period begins and continue to vest, employment continuation period.

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Grants in Period, Performance Target, Percentage

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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.

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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.

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- Definition

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

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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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.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

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

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No definition available.

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Equity Awards - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($) incentive_plan shares	Mar. 31, 2018 USD ($)	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans \| incentive_plan	2
Fair value of stock options vested	$ 2.0
Total unrecognized compensation cost, adjusted for estimated forfeitures, related to unvested stock options	$ 9.8
Options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted-average period	2 years 1 month 2 days
Restricted stock units with service condition only
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares outstanding (in shares) \| shares	11,167,127
Restricted stock units with service and performance conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares outstanding (in shares) \| shares	994,854
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted-average period	3 years 2 months 26 days
Number of shares outstanding (in shares) \| shares	12,161,981		10,201,660
Unrecognized compensation expense expected to be recognized	$ 1,500.0
Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares eligible to vest (percent)	100.00%
Stock-based compensation expense, net of actual and estimated forfeitures	$ 22.6	$ 15.6
Performance-based RSUs \| Vesting, tranche one
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	33.00%
Performance-based RSUs \| Vesting, tranche two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term	2 years
Performance-based RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares eligible to vest (percent)	0.00%
Performance-based RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares eligible to vest (percent)	180.00%
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock outstanding, increase, percentage	5.00%
2012 Equity Incentive Plan \| Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term	4 years
2012 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock outstanding, increase, percentage	1.00%
Common stock purchase price percentage	85.00%
Award offering period	6 months
2005 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to new employees vest, percentage per annum	25.00%
Requisite service period to vest employment continuation period	3 years
Options granted, exercisable period	10 years