INVESTMENT SECURITIES - Portfolio of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Held-to-maturity:
Amortized Cost	$ 98,211	$ 116,792
Gross Unrealized Gains	735	1,404
Gross Unrealized Losses	685	498
Fair Value	98,261	117,698
Obligations of state and political subdivisions
Held-to-maturity:
Amortized Cost	40,515	43,737
Gross Unrealized Gains	309	697
Gross Unrealized Losses	39	6
Fair Value	40,785	44,428
GSE mortgage-backed securities
Held-to-maturity:
Amortized Cost	44,375	55,696
Gross Unrealized Gains	426	705
Gross Unrealized Losses	311	131
Fair Value	44,490	56,270
Collateralized mortgage obligations: residential
Held-to-maturity:
Amortized Cost	8,969	10,803
Gross Unrealized Gains	0	0
Gross Unrealized Losses	323	361
Fair Value	8,646	10,442
Collateralized mortgage obligations: commercial
Held-to-maturity:
Amortized Cost	4,352	6,556
Gross Unrealized Gains	0	2
Gross Unrealized Losses	12	0
Fair Value	$ 4,340	$ 6,558

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.6)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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