SECURITIES - Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 322,437	$ 321,151
Gross Unrealized Gains	3,720	1,564
Gross Unrealized Losses	(2,301)	(6,260)
Fair Value	323,856	316,455
U.S. Government and agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,496	5,883
Gross Unrealized Gains	302	266
Gross Unrealized Losses	(18)	0
Fair Value	8,780	6,149
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	237,342	242,501
Gross Unrealized Gains	2,999	956
Gross Unrealized Losses	(1,969)	(5,655)
Fair Value	238,372	237,802
Agency mortgage-backed pass-through securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	30,183	27,496
Gross Unrealized Gains	222	265
Gross Unrealized Losses	(273)	(437)
Fair Value	30,132	27,324
Corporate bonds and other
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	46,416	45,271
Gross Unrealized Gains	197	77
Gross Unrealized Losses	(41)	(168)
Fair Value	$ 46,572	$ 45,180

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 2
-Subparagraph (c)
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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