Loans and Allowance for Credit Losses - Loans Restructured as TDRs, Excluding Loans Acquired, Segregated by Class of Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	5	4
Balance Prior to TDR	$ 1,948	$ 997
Financial Impact on Date of Restructure		$ 0
Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	54	56
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	5	4
Balance Prior to TDR	$ 1,948	$ 997
Balance	1,896	996
Financial Impact on Date of Restructure	$ 0	$ 0
Real Estate \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	48	49
Real Estate \| Change in Maturity Date
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	$ 1,896	$ 996
Real Estate \| Change in Rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	$ 0	$ 0
Real Estate \| Construction and development \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan		1
Real Estate \| Single family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	5	4
Balance Prior to TDR	$ 1,948	$ 997
Balance	1,896	996
Financial Impact on Date of Restructure	$ 0	$ 0
Real Estate \| Single family residential \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	46	45
Real Estate \| Single family residential \| Change in Maturity Date
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	$ 1,896	$ 996
Real Estate \| Single family residential \| Change in Rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	$ 0	0
Real Estate \| Other commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance Prior to TDR		$ 690
Real Estate \| Other commercial \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	2	3
Commercial \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	6	7
Commercial \| Commercial \| Loans, Excluding Acquired Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of TDR loans \| loan	6	7

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+ References

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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