Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Subsequently Defaulted (Details) - Troubled Debt Restructurings [Member] $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) Contract	Mar. 31, 2019 USD ($) Contract
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	6	12
Recorded Investment \| $	$ 640	$ 15,912
Construction, Land Development and Other Land [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	1
Recorded Investment \| $	$ 0	$ 22
Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	3	3
Recorded Investment \| $	$ 446	$ 684
Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	3	6
Recorded Investment \| $	$ 194	$ 15,178
Consumer Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	0	2
Recorded Investment \| $	$ 0	$ 28

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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=118936363&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=118936363&loc=SL6953682-111524

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