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Loans and Allowance for Credit Losses - Loans Individually and Collectively Evaluated for Impairment Prior to Adoption of ASU 2016-13 (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		$ 18,028
Loan Evaluation, Collectively		1,426,022
Total portfolio loans	$ 1,548,924	1,444,050
ALLL Allocations, Individually		13
ALLL Allocations, Collectively		21,123
ALLL Allocations, Total	14,764	21,136	$ 21,017	$ 19,088
Commercial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		7,786
Loan Evaluation, Collectively		764,682
Total portfolio loans	695,797	772,468
ALLL Allocations, Individually		13
ALLL Allocations, Collectively		7,960
ALLL Allocations, Total	4,269	7,973	8,269	6,604
Real estate construction one-to-four family
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		702
Loan Evaluation, Collectively		37,478
Total portfolio loans		38,180
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		679
ALLL Allocations, Total		679	643	643
Real estate construction other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		0
Loan Evaluation, Collectively		79,403
Total portfolio loans		79,403
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		1,179
ALLL Allocations, Total		1,179	1,279	1,017
Real estate term owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		6,962
Loan Evaluation, Collectively		155,762
Total portfolio loans		162,724
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		2,625
ALLL Allocations, Total		2,625	2,430	2,188
Real estate term non-owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		770
Loan Evaluation, Collectively		306,477
Total portfolio loans		307,247
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		5,133
ALLL Allocations, Total		5,133	5,491	5,180
Real estate term other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		1,467
Loan Evaluation, Collectively		44,763
Total portfolio loans		46,230
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		779
ALLL Allocations, Total		779	711	671
Consumer secured by 1st deeds of trust
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		259
Loan Evaluation, Collectively		15,289
Total portfolio loans		15,548
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		261
ALLL Allocations, Total		261	274	270
Consumer other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		82
Loan Evaluation, Collectively		22,168
Total portfolio loans		22,250
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		400
ALLL Allocations, Total		400	453	436
Other loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan Evaluation, Individually		0
Loan Evaluation, Collectively		0
Total portfolio loans	3,379	0
ALLL Allocations, Individually		0
ALLL Allocations, Collectively		2,107
ALLL Allocations, Total	$ 3	$ 2,107	$ 1,467	$ 2,079