Loans and Allowance for Loan Losses - Nonaccrual loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	$ 61,700	$ 59,460
Recorded Investment With No Allowance	14,924	10,714
Gross Recorded Investment With Allowance	43,608	46,304
Total Recorded Investment	58,532	57,018
Related Allowance	1,346	1,628
Average Investment In Impaired Loans	57,775	60,221	$ 42,318
Interest Income Recognized	2,134	2,068	1,984
Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	22,302	14,827
Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	10,839	13,489
Commercial non-owner occupied real estate \| Construction and land development
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	35,577	38,314
Recorded Investment With No Allowance	223	339
Gross Recorded Investment With Allowance	34,978	37,574
Total Recorded Investment	35,201	37,913
Related Allowance	617	788
Average Investment In Impaired Loans	36,556	40,571	23,132
Interest Income Recognized	1,014	1,201	1,138
Commercial non-owner occupied real estate \| Other commercial non-owner occupied real estate
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	385	1,157
Recorded Investment With No Allowance	368	536
Gross Recorded Investment With Allowance	11	489
Total Recorded Investment	379	1,025
Related Allowance		70
Average Investment In Impaired Loans	702	1,200	1,091
Interest Income Recognized	15	28	45
Commercial non-owner occupied real estate \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	1,095	1,255
Commercial non-owner occupied real estate \| Non acquired non-accrual loans \| Construction and land development
Loans and Allowance for Loan Losses
Nonaccrual loans	363	424
Commercial non-owner occupied real estate \| Non acquired non-accrual loans \| Other commercial non-owner occupied real estate
Loans and Allowance for Loan Losses
Nonaccrual loans	732	831
Commercial non-owner occupied real estate \| Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	1,092	535
Commercial non-owner occupied real estate \| Acquired non-credit impaired non-accrual loans \| Construction and land development
Loans and Allowance for Loan Losses
Nonaccrual loans	699	252
Commercial non-owner occupied real estate \| Acquired non-credit impaired non-accrual loans \| Other commercial non-owner occupied real estate
Loans and Allowance for Loan Losses
Nonaccrual loans	393	283
Commercial owner occupied real estate loan
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	7,689	5,085
Recorded Investment With No Allowance	4,836	3,101
Gross Recorded Investment With Allowance	1,739	1,041
Total Recorded Investment	6,575	4,142
Related Allowance	24	27
Average Investment In Impaired Loans	5,358	4,892	5,943
Interest Income Recognized	370	288	268
Commercial owner occupied real estate loan \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	3,482	1,068
Commercial owner occupied real estate loan \| Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	903	1,470
Consumer loans \| Home equity loans
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	2,605	2,953
Recorded Investment With No Allowance	1,184	1,129
Gross Recorded Investment With Allowance	1,277	1,697
Total Recorded Investment	2,461	2,826
Related Allowance	132	142
Average Investment In Impaired Loans	2,644	2,919	2,343
Interest Income Recognized	138	126	113
Consumer loans \| Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	5,410	7,291
Recorded Investment With No Allowance	1,969	4,992
Gross Recorded Investment With Allowance	3,172	1,769
Total Recorded Investment	5,141	6,761
Related Allowance	102	41
Average Investment In Impaired Loans	5,951	6,197	5,653
Interest Income Recognized	185	212	195
Consumer loans \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	8,670	9,442
Consumer loans \| Non acquired non-accrual loans \| Home equity loans
Loans and Allowance for Loan Losses
Nonaccrual loans	1,468	2,333
Consumer loans \| Non acquired non-accrual loans \| Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Nonaccrual loans	7,202	7,109
Consumer loans \| Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	5,417	8,376
Consumer loans \| Acquired non-credit impaired non-accrual loans \| Home equity loans
Loans and Allowance for Loan Losses
Nonaccrual loans	3,067	4,512
Consumer loans \| Acquired non-credit impaired non-accrual loans \| Consumer Owner Occupied Loans
Loans and Allowance for Loan Losses
Nonaccrual loans	2,350	3,864
Commercial and industrial
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	7,378	1,332
Recorded Investment With No Allowance	5,929	467
Gross Recorded Investment With Allowance	649	824
Total Recorded Investment	6,578	1,291
Related Allowance	366	416
Average Investment In Impaired Loans	3,935	1,224	1,209
Interest Income Recognized	324	57	48
Commercial and industrial \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	4,092	647
Commercial and industrial \| Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	722	1,296
Other income producing property
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	2,423	3,117
Recorded Investment With No Allowance	415	150
Gross Recorded Investment With Allowance	1,609	2,722
Total Recorded Investment	2,024	2,872
Related Allowance	50	142
Average Investment In Impaired Loans	2,448	3,005	2,755
Interest Income Recognized	84	155	171
Other income producing property \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	798	500
Other income producing property \| Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	1,101	244
Consumer
Loans and Allowance for Loan Losses
Unpaid Contractual Principal Balance	233	211
Gross Recorded Investment With Allowance	173	188
Total Recorded Investment	173	188
Related Allowance	55	2
Average Investment In Impaired Loans	181	213	192
Interest Income Recognized	4	1	$ 6
Consumer \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	1,587	1,267
Consumer \| Acquired non-credit impaired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	$ 1,604	1,568
Restructured loans \| ASC Topic 31020 Loans \| Minimum
Loans and Allowance for Loan Losses
Number of months generally required to return to accruing status	6 months
Restructured loans \| Non acquired non-accrual loans
Loans and Allowance for Loan Losses
Nonaccrual loans	$ 2,578	$ 648

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