Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) - Troubled Debt Restructurings [Member] $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($) Contract	Jun. 30, 2020 USD ($) Contract
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	3	5
Recorded Investment \| $	$ 5,007	$ 641
Other Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	3
Recorded Investment \| $	$ 0	$ 420
Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	1
Recorded Investment \| $	$ 0	$ 139
Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	1
Recorded Investment \| $	$ 0	$ 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	0
Recorded Investment \| $	$ 78	$ 0
Other Commercial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	2	0
Recorded Investment \| $	$ 4,929	$ 0

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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=121611835&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=121611835&loc=SL6953682-111524

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