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STOCKHOLDERS' EQUITY - EMPLOYEE STOCK PURCHASE PLAN (Details) - Employee Stock Purchase Plan	12 Months Ended
	Dec. 31, 2017 item shares
Employee Stock Purchase Plan
Shares of common stock authorized for issuance | shares	1,000,000
Aggregate shares issued under plan | shares	104,692
Maximum duration of offering period	12 months
Number of offering periods in which an employee can participate at a time | item	1
Number of consecutive purchase periods in an offering period | item	2
Duration of the purchase period	6 months
Maximum percentage of annual salary that can be withheld	10.00%
Percentage applied to common stock market value in calculating purchase price under purchase plan	85.00%
Duration of the new offering period	12 months

X

- Definition

Represents the aggregate number of share instruments issued under a share-based compensation plan.

+ References

No definition available.

+ Details

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X

- Definition

Represents the duration of new offering period in a case where the fair market value of common stock on the purchase date is less than the fair market value at the beginning of the offering period.

+ References

No definition available.

+ Details

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- Definition

Represents the duration of the purchase period under the employee stock purchase plan.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum duration of the offering period under the employee stock purchase plan.

+ References

No definition available.

+ Details

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X

- Definition

Represents the number of offering periods in which an employee can participate at a time in the purchase plan.

+ References

No definition available.

+ Details

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X

- Definition

Represents the maximum percentage of annual salary that an employee can choose to have withheld to purchase common stock under the purchase plan.

+ References

No definition available.

+ Details

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X

- Definition

Represents the number of consecutive purchase periods in an offering period in the purchase plan.

+ References

No definition available.

+ 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

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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