Investment Securities - Available-for-sale (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	$ 187,310	$ 165,032
Unrealized Gain	1,832	1,146
Unrealized Loss	(1,794)	(3,810)
Fair Value	187,348	162,368
Total debt securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	172,319	157,389
Unrealized Gain	1,207	765
Unrealized Loss	(1,794)	(3,810)
Fair Value	171,732	154,344
U. S. Agency securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	55,895	29,234
Unrealized Gain	69	7
Unrealized Loss	(347)	(425)
Fair Value	55,617	28,816
U.S. Sponsored Mortgage-backed securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	55,602	56,080
Unrealized Gain	61	14
Unrealized Loss	(944)	(1,362)
Fair Value	54,719	54,732
Municipal securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	60,822	72,075
Unrealized Gain	1,077	744
Unrealized Loss	(503)	(2,023)
Fair Value	61,396	70,796
Equity and other securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	14,991	7,643
Unrealized Gain	625	381
Unrealized Loss	0	0
Fair Value	$ 15,616	$ 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
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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
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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
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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