Investment Securities - Amortized Costs, Gains and Losses, Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	$ 221,167	$ 222,578
Gross Unrealized Gains	235	123
Gross Unrealized Losses	(2,863)	(4,496)
Fair value	218,539	218,205
U.S. Treasury
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	2,666	1,984
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(11)	(32)
Fair value	2,655	1,952
U.S. government and federal agency obligations
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	9,745	10,235
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(230)	(269)
Fair value	9,515	9,966
Government sponsored enterprises
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	39,790	43,784
Gross Unrealized Gains	43	23
Gross Unrealized Losses	(279)	(472)
Fair value	39,554	43,335
Obligations of states and political subdivisions
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	38,408	40,859
Gross Unrealized Gains	67	28
Gross Unrealized Losses	(239)	(501)
Fair value	38,236	40,386
Mortgage-backed securities
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	126,072	121,230
Gross Unrealized Gains	125	72
Gross Unrealized Losses	(1,954)	(3,110)
Fair value	124,243	118,192
Other debt securities
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	3,000	3,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Fair value	2,999	3,000
Bank issued trust preferred securities
Amortized cost and fair value of debt securities available-for-sale
Total Amortized Cost	1,486	1,486
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(149)	(112)
Fair value	$ 1,337	$ 1,374

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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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

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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