Loans and Allowance for Credit Losses - Loans Restructured as TDRs, Excluding Loans Acquired, Segregated by Class of Loans (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($) loan	Sep. 30, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1	5
Balance Prior to TDR	$ 784	$ 1,900
Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1	5
Balance Prior to TDR	$ 784	$ 1,948
Balance	778	1,896
Financial Impact on Date of Restructure	0	0
Real Estate \| Change in Maturity Date
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	1,896
Real Estate \| Change in Rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 778	$ 0
Real Estate \| Other commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan	1
Balance Prior to TDR	$ 784
Balance	778
Financial Impact on Date of Restructure	0
Real Estate \| Other commercial \| Change in Maturity Date
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0
Real Estate \| Other commercial \| Change in Rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 778
Real Estate \| Single family residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans \| loan		5
Balance Prior to TDR		$ 1,948
Balance		1,896
Financial Impact on Date of Restructure		0
Real Estate \| Single family residential \| Change in Maturity Date
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		1,896
Real Estate \| Single family residential \| Change in Rate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		$ 0

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- Definition

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+ References

No definition available.

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- Definition

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=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

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