The reduction in number of available shares when a share is issued under the share based compensation.

No definition available.

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- Definition

The offering period of the employee stock purchase plan ("ESPP").

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Amount

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Available For Purchase

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-SubTopic 10
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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 highest quantity of shares an employee can purchase under the plan per period.

+ References

+ Details

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

+ Details

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Number of shares purchased for issuance under share-based payment arrangement.

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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.

+ References

No definition available.

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STOCK-BASED COMPENSATION - NARRATIVE (Details)		9 Months Ended
STOCK-BASED COMPENSATION - NARRATIVE (Details)	Jun. 14, 2019 shares	Sep. 30, 2019 USD ($) shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of available shares consumed for each restricted stock and restricted stock units issued		1.75
Unrecognized compensation cost \| $		$ 9,300,000
Unrecognized compensation cost, recognized over an estimated weighted-average period		2 years 9 months 11 days
Stock options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		4 years
Increase in number of common shares reserved for issuance (in shares)	2,595,751
Stock options outstanding (in shares)		2,011,000
Stock options outstanding \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award expiration period		7 years
Stock options outstanding \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award expiration period		10 years
RSAs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		1 year
RSUs outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based payment award vesting period		3 years
Market condition based stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)		272,081	272,081
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value on the purchase date		85.00%
Maximum number of shares per employee (in shares)		2,000
Employee stock purchase plan offering period		6 months
Maximum value of shares per employee \| $		$ 25,000
Common stock reserved for issuance (in shares)		1,000,000
Purchases under ESPP (in shares)		21,741
Shares available for purchase (in shares)		253,437