ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY OF FINANCING RECEIVABLES - Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) property loan	Mar. 31, 2018 loan	Dec. 31, 2018 USD ($) property
Financing Receivable, Modifications [Line Items]
Number of loans modified by troubled debt restructuring \| loan	2
Number of loans with subsequent default \| loan	0	0
Foreclosed real estate	$ 3,241		$ 4,149
Carrying value of collateralized consumer loans	$ 1,514,752		$ 1,475,827
Residential Real Estate
Financing Receivable, Modifications [Line Items]
Number of foreclosed properties \| property	4		5
Foreclosed real estate	$ 1,000		$ 1,300
Consumer and Other
Financing Receivable, Modifications [Line Items]
Carrying value of collateralized consumer loans	$ 504		$ 682

Real Estate Acquired Through Foreclosure, Number

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+ References

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04(c)(Schedule III))
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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-Section 50
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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