DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Summary of Derivative Financial Instruments (Details) - Mortgages - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other Assets
Derivative [Line Items]
Derivative, notional amount	$ 117,649	$ 241,426
Derivative, fair value	2,888	4,314
Other Liabilities
Derivative [Line Items]
Derivative, notional amount	126,750	0
Derivative, fair value	67	0
Forward contracts related to mortgage loans held for sale
Derivative [Line Items]
Derivative, notional amount	158,300	150,000
Forward contracts related to mortgage loans held for sale \| Other Assets
Derivative [Line Items]
Derivative, notional amount	31,500	150,000
Derivative, fair value	55	1,285
Forward contracts related to mortgage loans held for sale \| Other Liabilities
Derivative [Line Items]
Derivative, notional amount	126,750	0
Derivative, fair value	67	0
Interest rate lock commitments \| Other Assets
Derivative [Line Items]
Derivative, notional amount	86,149	91,426
Derivative, fair value	$ 2,833	$ 3,029

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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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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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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