Defined Contribution Plan, Employee Contributions, Percentage of Eligible Compensation

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- Definition

Number of shares available to issuance under the employee stock purchase plan.

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Net number of share options (or share units) granted during the period to non-employees.

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- Definition

Share based compensation employee stock purchase plan contribution percentage.

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- Definition

The number of share available for issuance.

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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

Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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No definition available.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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No definition available.

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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

Unrecognized cost of unvested options awarded to employees as compensation.

+ 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.

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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

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 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.

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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

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Percentage of vesting of share-based compensation awards.

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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

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

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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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Share-Based Compensation and Employee Benefit Plans - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	May 16, 2018	Dec. 31, 2015	Nov. 01, 2009
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share authorized available for grants						3,300,000
Common stock available for future grant	2,558,000
Share based compensation shares for issuance	0	2,049,000
Total intrinsic value of stock options exercised	$ 384,000	$ 853,000	$ 1,312,000
Options outstanding exercise price	$ 12.22	$ 12.22	$ 10.19		$ 9.46
Options exercisable exercise price	$ 12.22
Unrecognized compensation cost - option	$ 0
Fair value of outstanding stock options to non-employees	$ 126,000	$ 268,000
Price of common stock as percentage of fair market value	95.00%
Stock based compensation expense	$ 6,062,000	$ 5,670,000	$ 4,775,000
Shares purchased under ESPP	13,000	11,000	15,000
Employee Stock Purchase Plan available	1,500,000	2,251,000
Percentage of contribution for annual compensation	100.00%
Percentage of match of all employee contribution	50.00%
Total matching contribution to plan	$ 1,118,000	$ 1,047,000	$ 1,017,000
Defined contribution plan, employer contribution under profit sharing program	0	0	0
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expense	$ 0	0	0
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Eligible compensation deduction percentage on pay for purchase of common stock	15.00%
Percentage of match on employee salary	6.00%
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	5 years
Options expiration period	10 years
Stock based compensation expense		$ 237,000	$ 318,000
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to restricted stock units granted	$ 9,517,000
Unrecognized compensation cost related to restricted stock units, weighted average period	2 years 1 month 6 days
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	3 years
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	5 years
Restricted Stock Units (RSUs) [Member] \| Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	1 year
Market Performance Based Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	3 years
Maximum potential market performance-based restricted stock units to vest percentage	200.00%
2018 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share authorized available for grants				3,240,000
Common stock available for future grant	128,000
Share based compensation shares for issuance	3,332,000
2018 Plan [Member] \| Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	5 years
Options expiration period	10 years
2018 Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	3 years
2018 Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	5 years
2018 Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Director [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	1 year