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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Total	$ 88,874		$ 76,733
Allowance for Loan Losses, LHFI [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	15,749		1,743
Collectively	73,125		74,990
Total	88,874	$ 83,566	76,733	$ 80,332	$ 76,184	$ 71,265
Allowance for Loan Losses, LHFI [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	13,869		131
Collectively	19,448		22,720
Total	33,317		22,851	19,780		22,011
Allowance for Loan Losses, LHFI [Member] \| Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively	3,394		3,470
Total	3,394		3,470	4,456		3,241
Allowance for Loan Losses, LHFI [Member] \| State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	683
Collectively	510		789
Total	1,193		789	811		859
Allowance for Loan Losses, LHFI [Member] \| Other Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	1,076		41
Collectively	4,364		4,625
Total	5,440		4,666	4,204		2,492
Allowance for Loan Losses, LHFI [Member] \| Loans Secured by Real Estate [Member] \| Construction, Land Development and Other Land [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually			75
Collectively	8,414		7,790
Total	8,414		7,865	8,648		9,085
Allowance for Loan Losses, LHFI [Member] \| Loans Secured by Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	43		1,331
Collectively	9,265		9,543
Total	9,308		10,874	10,280		10,347
Allowance for Loan Losses, LHFI [Member] \| Loans Secured by Real Estate [Member] \| Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually	78		165
Collectively	24,781		23,263
Total	24,859		23,428	28,748		20,967
Allowance for Loan Losses, LHFI [Member] \| Loans Secured by Real Estate [Member] \| Other Real Estate Secured [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively	2,949		2,790
Total	$ 2,949		$ 2,790	$ 3,405		$ 2,263