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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recent Accounting Pronouncements (Details) $ in Thousands	Dec. 31, 2018 USD ($) lease	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Equity investment portfolio balance		$ 400	$ 500
Right of use leased asset		$ 5,572	$ 3,537
Scenario, Forecast | Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use leased asset	$ 5,000
Number of leased facilities | lease	13

X

- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

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- Definition

The number of units (items of property) under capital lease arrangements.

+ References

No definition available.

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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