ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY - Troubled Debt Restructurings Subsequently Defaulted (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($) item
Troubled Debt Restructurings
Troubled Debt Restructurings, Subsequently Defaulted , Number of Loans \| item	1	0
Troubled Debt Restructurings, Subsequently Defaulted, Recorded Investment \| $	$ 601	$ 0	$ 0
Non-working capital loans \| Commercial and Industrial Loans
Troubled Debt Restructurings
Troubled Debt Restructurings, Subsequently Defaulted , Number of Loans \| item	1	0	0
Troubled Debt Restructurings, Subsequently Defaulted, Recorded Investment \| $	$ 601	$ 0	$ 0

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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