Securities - Amortized Cost and Approximate Fair Values, Together with Gross Unrealized Gains and Losses of Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Amortized Cost	$ 180,397	$ 123,333
Available-for-sale Securities, Gross Unrealized Gains	9,029	1,194
Available-for-sale Securities, Gross Unrealized Losses	(641)	(536)
Available-for-sale securities, Fair Value	188,785	123,991
U.S. government agencies
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Amortized Cost	40,000	45,250
Available-for-sale Securities, Gross Unrealized Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	(472)	(500)
Available-for-sale securities, Fair Value	39,528	44,750
Subordinated notes
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Amortized Cost	4,500
Available-for-sale Securities, Gross Unrealized Gains	36
Available-for-sale Securities, Gross Unrealized Losses	(4)
Available-for-sale securities, Fair Value	4,532
State and municipal obligations
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Amortized Cost	135,897	78,083
Available-for-sale Securities, Gross Unrealized Gains	8,993	1,194
Available-for-sale Securities, Gross Unrealized Losses	(165)	(36)
Available-for-sale securities, Fair Value	$ 144,725	$ 79,241

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=118939692&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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

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-Name Accounting Standards Codification
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Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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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 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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