LHFI and Allowance for Loan Losses, LHFI - Troubled Debt Restructuring Related to Loans Held for Investment, Excluding Covered Loans, by Loan Type (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable Modifications [Line Items]
Nonaccrual	$ 55,312	$ 79,343
Construction, Land Development and Other Land [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	6,123	13,867
Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	23,079	25,621
Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	17,800	25,717
Other Real Estate Secured [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	145	1,318
Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	7,622	12,104
Troubled Debt Restructurings [Member]
Financing Receivable Modifications [Line Items]
Accruing	2,235	1,385	$ 1,320
Nonaccrual	7,418	9,910	13,456
Total	9,653	11,295	14,776
Troubled Debt Restructurings [Member] \| Construction, Land Development and Other Land [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	0	0	0
Nonaccrual	869	3,665	6,247
Total	869	3,665	6,247
Troubled Debt Restructurings [Member] \| Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	1,426	1,385	1,320
Nonaccrual	2,424	3,733	4,201
Total	3,850	5,118	5,521
Troubled Debt Restructurings [Member] \| Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	809	0	0
Nonaccrual	3,662	1,854	2,292
Total	4,471	1,854	2,292
Troubled Debt Restructurings [Member] \| Other Real Estate Secured [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing		0	0
Nonaccrual		149	167
Total		149	167
Troubled Debt Restructurings [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Accruing	0	0	0
Nonaccrual	463	509	549
Total	$ 463	$ 509	$ 549

Recorded investment in TDR's that are still accruing.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

+ Details

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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