ALLOWANCE FOR CREDIT LOSSES - Allowance for credit losses for unfunded commitments (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Beginning balance	$ 25,280
Ending balance	39,678
Unfunded Commitment
Financing Receivable, Recorded Investment [Line Items]
Beginning balance	378
Impact of implementation	2,981
Provision for credit losses for unfunded commitments	1,643
Ending balance	$ 5,002

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant