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	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Financing Receivable Modifications [Line Items]
Nonaccrual	$ 70,694	$ 55,312
Construction, Land Development and Other Land [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	6,308	6,123
Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	23,660	23,079
Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	22,141	17,800
Other Real Estate Secured [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	93	145
Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Nonaccrual	17,827	7,622
Troubled Debt Restructurings [Member]
Financing Receivable Modifications [Line Items]
Accruing	2,243		$ 2,311
Nonaccrual	6,945	$ 7,400	8,472
Total	9,188		10,783
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
Nonaccrual	845		3,086
Total	845		3,086
Troubled Debt Restructurings [Member] \| Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	1,444		1,477
Nonaccrual	2,086		3,605
Total	3,530		5,082
Troubled Debt Restructurings [Member] \| Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable Modifications [Line Items]
Accruing	799		834
Nonaccrual	3,566		1,121
Total	4,365		1,955
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
Total			149
Troubled Debt Restructurings [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Modifications [Line Items]
Accruing	0		0
Nonaccrual	448		511
Total	$ 448		$ 511

Recorded investment in TDR's that are still accruing.

No definition available.

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Balance Type:	debit
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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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