Noninterest Income - Summary of Noninterest Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation Of Revenue [Line Items]
Earnings and gain on bank owned life insurance	$ 133	$ 138	$ 355	$ 319
Net gains (losses) on sales and redemptions of investment securities	121	(60)	232	(189)
Gains on marketable equity securities	4		61	26
Other miscellaneous income	21	29	83	119
Total noninterest income	1,286	940	3,598	2,859
Insufficient Funds Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	347	218	827	618
Deposit Related Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	28	49	133	148
ATM Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	24	24	69	72
Service Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	399	291	1,029	838
Insurance Commissions [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	168	172	620	632
Investment Services Revenue [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	58	70	203	218
ATM Fees Surcharge [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	68	71	173	178
Banking House Rents Collected [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	32	34	100	100
Fee Income [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	326	347	1,096	1,128
Debit Card Interchange Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	166	141	497	432
Merchant Card Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	21	21	58	54
Card Income [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	187	162	555	486
Loan Servicing Fees [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	57	25	144	108
Net Gains on Sale of Loans and Foreclosed Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	38	8	43	24
Total Mortgage Fee Income and Realized Gain on Sale of Loans and Foreclosed Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	95	33	187	132
Service Fees, Fee Income, Card Income and Mortgage Fee Income and Realized Gain on Sale of Loans and Foreclosed Real Estate [Member]
Disaggregation Of Revenue [Line Items]
Noninterest income	$ 1,007	$ 833	$ 2,867	$ 2,584

Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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Represents the total of noninterest income derived from certain activities and assets including (for example): (1) venture capital investments; (2) bank owned life insurance; (3) foreign currency transactions; and (4) mortgage servicing rights.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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