Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) - Troubled Debt Restructurings [Member] $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($) Contract	Sep. 30, 2020 USD ($) Contract
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	9	6
Recorded Investment \| $	$ 10,605	$ 705
Construction, Land Development and Other Land [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	5
Recorded Investment \| $	$ 5,582
Other Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	1	4
Recorded Investment \| $	$ 16	$ 484
Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract		1
Recorded Investment \| $		$ 139
Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract		1
Recorded Investment \| $		$ 82
Secured by 1-4 Family Residential Properties [Member] \| Other Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	1
Recorded Investment \| $	$ 78
Other Commercial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	2
Recorded Investment \| $	$ 4,929

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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