Investment Securities - Available-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	$ 231,419	$ 231,514
Unrealized Gain	1,174	2,489
Unrealized Loss	(6,089)	(2,496)
Fair Value	226,504	231,507
Total debt securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	222,184	215,574
Unrealized Gain	1,087	1,845
Unrealized Loss	(6,053)	(2,478)
Fair Value	217,218	214,941
U. S. Agency securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	82,518	81,705
Unrealized Gain	91	81
Unrealized Loss	(1,814)	(841)
Fair Value	80,795	80,945
U.S. Sponsored Mortgage-backed securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	58,827	59,387
Unrealized Gain	0	31
Unrealized Loss	(2,509)	(1,264)
Fair Value	56,318	58,154
Municipal securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	80,839	74,482
Unrealized Gain	996	1,733
Unrealized Loss	(1,730)	(373)
Fair Value	80,105	75,842
Other securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	9,235
Unrealized Gain	87
Unrealized Loss	(36)
Fair Value	$ 9,286
Equity and other securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost		15,940
Unrealized Gain		644
Unrealized Loss		(18)
Fair Value		$ 16,566

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

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

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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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

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-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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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-Subparagraph (b)-(g)
-URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62557-112803

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