SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill
Goodwill, Beginning Balance	$ 2,375	$ 3,283
Impairment of Goodwill	0	(908)
Goodwill, Ending Balance	2,375	2,375
Fair Value of Goodwill
Impairment of Goodwill	$ 0	908
Nonrecurring fair value
Goodwill
Impairment of Goodwill		(908)
Fair Value of Goodwill
Goodwill		2,375
Impairment of Goodwill		908
Nonrecurring fair value \| Significant unobservable inputs (Level 3)
Fair Value of Goodwill
Goodwill		$ 2,375

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
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- Definition

Fair value portion of asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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