INDEMNIFICATIONS AND GUARANTEES (Details)	9 Months Ended
Sep. 30, 2018 USD ($) loan Transaction Financial_Institution	Dec. 31, 2017 USD ($) loan
Guarantor Obligations [Line Items]
Number of unrelated financial institutions \| Financial_Institution	5
Derivative transaction held for guarantee \| loan	135	134
Notional	$ 199,330,000
Aggregate fair value of swaps to customers, asset	9,800,000
Aggregate fair value of swaps to customers, liability		$ 3,300,000
Reserves for swap guarantees	$ 0
Minimum
Guarantor Obligations [Line Items]
Notional amount maturity period	1 year
Maximum
Guarantor Obligations [Line Items]
Notional amount maturity period	10 years
Secondary Market Loan Sales
Guarantor Obligations [Line Items]
Provision for losses at the time of sale	$ 0
Number of loans repurchased \| Transaction	0
Interest Rate Swap
Guarantor Obligations [Line Items]
Notional	$ 571,700,000	$ 561,800,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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- Definition

The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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- Definition

Amount of expense related to loss from loan transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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Number Of Financial Institutions

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Number Of Loans Repurchased

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- Definition

Reserves For Swap Guarantees

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