SIGNIFICANT ACCOUNTING POLICIES - Stock-Based Compensation (Details)	12 Months Ended
Dec. 31, 2017 plan
Stock-Based Compensation
Number of stock-based compensation plans	1
Term of the absolute common stock price compounded annual growth rate	3 years
Restricted stock units \| Minimum
Stock-Based Compensation
Period for vesting of awards	1 year
Restricted stock units \| Maximum
Stock-Based Compensation
Period for vesting of awards	4 years

The number of share-based compensation plans maintained by the reporting entity as on the balance sheet date.

No definition available.

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- Definition

Represents the term of the absolute common stock price compounded annual growth rate ("CAGR").

+ References

No definition available.

+ Details

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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.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ 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.

+ Details

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- Details

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- Details

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