DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Economic Hedges and Non-hedging Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Hedging derivatives \| Economic Hedging \| Interest Rate Swap \| Industrial Revenue Bond
Derivative [Line Items]
Unrealized gain (loss) recognized in other non-interest income	$ (75)	$ (344)
Hedging derivatives \| Economic Hedging \| Interest Rate Swap \| Commercial loan
Derivative [Line Items]
Unrealized gain (loss) recognized in other non-interest income	1,312	(4,852)
Hedging derivatives \| Economic Hedging \| Reverse Interest Rate Swaps \| Commercial loan
Derivative [Line Items]
Unrealized gain (loss) recognized in other non-interest income	(1,312)	4,852
Favorable (unfavorable) change in credit valuation adjustment recognized in other non-interest income	338	(51)
Hedging derivatives \| Economic Hedging \| Risk Participation Agreements
Derivative [Line Items]
Unrealized gain (loss) recognized in other non-interest income	(61)	(36)
Hedging derivatives \| Economic Hedging \| Forward Commitments
Derivative [Line Items]
Unrealized gain (loss) recognized in other non-interest income	(1,176)	(247)
Realized gain (loss) in other non-interest income	(3,705)	45
Non-hedging derivatives \| Interest rate lock commitments
Derivative [Line Items]
Unrealized gain (loss) recognized in other non-interest income	8,373	2,436
Realized gain (loss) in other non-interest income	$ 3,650	$ 1,899

The favorable changes in credit valuation adjustments on derivative instruments that were recognized in other non-interest income during the current period.

No definition available.

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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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- Definition

Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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