Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) Contract	Dec. 31, 2019 USD ($) Contract	Dec. 31, 2018 USD ($) Contract
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	0	1
Recorded Investment \| $	$ 0	$ 0	$ 22
Troubled Debt Restructurings [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	4	11	13
Recorded Investment \| $	$ 299	$ 665	$ 15,935
Troubled Debt Restructurings [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	1	7	6
Recorded Investment \| $	$ 82	$ 192	$ 15,178
Troubled Debt Restructurings [Member] \| Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	2	3	5
Recorded Investment \| $	$ 78	$ 446	$ 734
Troubled Debt Restructurings [Member] \| Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	1	0	0
Recorded Investment \| $	$ 139	$ 0	$ 0
Troubled Debt Restructurings [Member] \| Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	1	1
Recorded Investment \| $	$ 0	$ 27	$ 1

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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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- Definition

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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