Loans, Allowance for Credit Losses and Impaired Loans - Impaired loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Impaired loans with specific reserves - Recorded Investment	$ 4,457	$ 7,267
Impaired loans with specific reserves - Unpaid Principal Balance	4,457	7,395
Impaired loans with specific reserves - Interest Income Recognized	313	422
Impaired loans with specific reserves - Specific Reserve	572	1,042
Impaired loans with specific reserves - Average Recorded Investment	5,862	8,701
Impaired loans with no specific reserves - Recorded Investment	15,608	20,415
Impaired loans with no specific reserves - Unpaid Principal Balance	15,615	22,721
Impaired loans with no specific reserves - Interest Income Recognized	1,290	1,384
Impaired loans with no specific reserves - Average Recorded Investment	18,010	15,673
Impaired loans specific reserves - Recorded Investment	20,065	27,682
Impaired loans specific reserves - Unpaid Principal Balance	20,072	30,116
Impaired loans specific reserves - Interest Income Recognized	1,603	1,806
Impaired loans specific reserves - Average Recorded Investment	23,872	24,374
Loans
Carrying amount	986,684	625,513
Unamortized discounts on acquired loans	6,136	1,327
PCI loans
Loans
Carrying amount	5,373	1,110
Unamortized discounts on acquired loans	812	582
Individual evaluation for impairment not required	946	1,100
Real Estate Mortgage \| Construction and Land Development
Financing Receivable, Impaired [Line Items]
Impaired loans with specific reserves - Average Recorded Investment		16
Impaired loans with no specific reserves - Recorded Investment	723	220
Impaired loans with no specific reserves - Unpaid Principal Balance	545	360
Impaired loans with no specific reserves - Interest Income Recognized	34	1
Impaired loans with no specific reserves - Average Recorded Investment	471	264
Real Estate Mortgage \| Residential Real Estate
Financing Receivable, Impaired [Line Items]
Impaired loans with specific reserves - Recorded Investment	727	3,947
Impaired loans with specific reserves - Unpaid Principal Balance	727	4,075
Impaired loans with specific reserves - Interest Income Recognized		174
Impaired loans with specific reserves - Specific Reserve	216	586
Impaired loans with specific reserves - Average Recorded Investment	2,337	4,934
Impaired loans with no specific reserves - Recorded Investment	4,064	5,068
Impaired loans with no specific reserves - Unpaid Principal Balance	4,717	6,318
Impaired loans with no specific reserves - Interest Income Recognized	243	228
Impaired loans with no specific reserves - Average Recorded Investment	4,566	3,555
Real Estate Mortgage \| Nonresidential
Financing Receivable, Impaired [Line Items]
Impaired loans with specific reserves - Recorded Investment	2,456	3,276
Impaired loans with specific reserves - Unpaid Principal Balance	2,456	3,276
Impaired loans with specific reserves - Interest Income Recognized	260	246
Impaired loans with specific reserves - Specific Reserve	82	412
Impaired loans with specific reserves - Average Recorded Investment	2,866	3,674
Impaired loans with no specific reserves - Recorded Investment	9,734	12,629
Impaired loans with no specific reserves - Unpaid Principal Balance	9,266	13,545
Impaired loans with no specific reserves - Interest Income Recognized	909	1,015
Impaired loans with no specific reserves - Average Recorded Investment	11,181	10,427
Real Estate Mortgage \| Home Equity Loans
Financing Receivable, Impaired [Line Items]
Impaired loans with specific reserves - Average Recorded Investment		55
Impaired loans with no specific reserves - Recorded Investment	9	693
Impaired loans with no specific reserves - Unpaid Principal Balance	9	693
Impaired loans with no specific reserves - Interest Income Recognized	17	28
Impaired loans with no specific reserves - Average Recorded Investment	351	347
Commercial
Financing Receivable, Impaired [Line Items]
Impaired loans with specific reserves - Recorded Investment	1,274	44
Impaired loans with specific reserves - Unpaid Principal Balance	1,274	44
Impaired loans with specific reserves - Interest Income Recognized	53	2
Impaired loans with specific reserves - Specific Reserve	274	44
Impaired loans with specific reserves - Average Recorded Investment	659	22
Impaired loans with no specific reserves - Recorded Investment	1,078	1,805
Impaired loans with no specific reserves - Unpaid Principal Balance	1,078	1,805
Impaired loans with no specific reserves - Interest Income Recognized	87	112
Impaired loans with no specific reserves - Average Recorded Investment	$ 1,441	$ 1,080

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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