INVESTMENT SECURITIES - Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	$ 231,514	$ 165,032
Unrealized Gain	2,489	1,146
Unrealized Loss	(2,496)	(3,810)
Fair Value	231,507	162,368
Total debt securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	215,574	157,389
Unrealized Gain	1,845	765
Unrealized Loss	(2,478)	(3,810)
Fair Value	214,941	154,344
U. S. Agency securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	81,705	29,234
Unrealized Gain	81	7
Unrealized Loss	(841)	(425)
Fair Value	80,945	28,816
U.S. Sponsored Mortgage-backed securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	59,387	56,080
Unrealized Gain	31	14
Unrealized Loss	(1,264)	(1,362)
Fair Value	58,154	54,732
Municipal securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	74,482	72,075
Unrealized Gain	1,733	744
Unrealized Loss	(373)	(2,023)
Fair Value	75,842	70,796
Equity and other securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	15,940	7,643
Unrealized Gain	644	381
Unrealized Loss	(18)	0
Fair Value	$ 16,566	$ 8,024

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=75030427&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
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-URI http://asc.fasb.org/extlink&oid=82897076&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=82896770&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
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+ 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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