SECURITIES - Securities with gross unrealized losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Investment securities
Fair value - Less than twelve months	$ 73,153	$ 134,561
Gross Unrealized loss - Less than twelve months	(561)	(2,658)
Fair value - Twelve months or more	62,560	313
Gross Unrealized loss - Twelve months or more	(1,485)	(3)
State and municipal securities
Investment securities
Fair value - Less than twelve months	2,494	22,856
Gross Unrealized loss - Less than twelve months	(3)	(647)
Fair value - Twelve months or more	6,516	313
Gross Unrealized loss - Twelve months or more	(115)	(3)
Debt securities
Investment securities
Fair value - Less than twelve months	4,464	18,341
Gross Unrealized loss - Less than twelve months	(55)	(454)
Fair value - Twelve months or more	12,481
Gross Unrealized loss - Twelve months or more	(315)
Collateralized mortgage obligations
Investment securities
Fair value - Less than twelve months	44,116	24,800
Gross Unrealized loss - Less than twelve months	(380)	(325)
Fair value - Twelve months or more	9,938
Gross Unrealized loss - Twelve months or more	(295)
Mortgage-backed securities
Investment securities
Fair value - Less than twelve months	22,079	67,500
Gross Unrealized loss - Less than twelve months	(123)	(1,215)
Fair value - Twelve months or more	32,538
Gross Unrealized loss - Twelve months or more	(743)
Other securities
Investment securities
Fair value - Less than twelve months		1,064
Gross Unrealized loss - Less than twelve months		$ (17)
Fair value - Twelve months or more	1,087
Gross Unrealized loss - Twelve months or more	$ (17)

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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- Definition

Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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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

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