Employee Stock Purchase Plan Contribution Percentage

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- Definition

Employee Stock Purchase Plan Offering Period

+ References

No definition available.

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- Definition

Employee Stock Purchase Plan Purchase Period

+ References

No definition available.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Plan Modification, Options, Number Of Shares Modified

+ References

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

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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 equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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

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).

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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.

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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.

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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.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

The number of employees affected by the modification of an equity-based compensation plan.

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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.

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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.

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-based Compensation - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Jul. 31, 2013	Dec. 31, 2017 USD ($) employee $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value per share (in dollars per share) \| $ / shares		$ 9.08	$ 6.79	$ 7.07
Aggregate intrinsic value for options exercised		$ 2,400,000	$ 5,000,000	$ 2,100,000
Fair value of options vested		8,900,000	6,800,000	6,500,000
Unrecognized compensation cost		$ 19,200,000
Unrecognized compensation cost, weighted-average recognized period		2 years 4 months 6 days
Tax benefit recognized related to share-based compensation cost		$ 0
Total share-based compensation expense		$ 11,369,000	9,038,000	$ 6,278,000
2004 Stock Option Plan and 2013 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under the Plans (in shares) \| shares		7,501,801
Stock options grant period, years		10 years
Stock options vesting period and exercisable period, years		4 years
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees affected \| employee		109
Number of shares modified \| shares		265,000
Incremental compensation cost		$ 50,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total value of shares vested		$ 1,083,000	$ 64,000
Shares vested (in shares) \| shares		66,956	0	0
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of offering period, in months	12 months
Length of purchase periods, in months	6 months
Purchase price percentage of fair market value of shares	85.00%
Shares issued (in shares) \| shares		138,972	139,195	136,078
Total share-based compensation expense		$ 800,000	$ 800,000	$ 400,000
Common stock reserved for issuance (in shares) \| shares		825,442
Share available for grant (in shares) \| shares		269,811
ESPP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contribution percentage of purchase shares on participants eligible compensation	0.00%
ESPP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contribution percentage of purchase shares on participants eligible compensation	10.00%