Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI (3) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Financing Receivable, Modifications [Line Items]
Nonaccrual	$ 61,131	$ 79,343
Construction, Land Development and Other Land [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual	8,748	13,867
Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual	22,342	25,621
Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual	20,465	25,717
Other Real Estate Secured [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual	434	1,318
Commercial and Industrial Loans [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual	8,571	12,104
Consumer Loans [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual	45	$ 88
Troubled Debt Restructurings [Member]
Financing Receivable, Modifications [Line Items]
Accruing	2,204		$ 1,373
Nonaccrual	8,969		10,619
Total	11,173		11,992
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	1,006		4,076
Total	1,006		4,076
Troubled Debt Restructurings [Member] \| Secured by 1-4 Family Residential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	1,385		1,373
Nonaccrual	2,921		3,940
Total	4,306		5,313
Troubled Debt Restructurings [Member] \| Secured by Nonfarm, Nonresidential Properties [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	819		0
Nonaccrual	4,503		1,923
Total	5,322		1,923
Troubled Debt Restructurings [Member] \| Other Real Estate Secured [Member] \| Loans Secured by Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Accruing	0		0
Nonaccrual	62		156
Total	62		156
Troubled Debt Restructurings [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable, Modifications [Line Items]
Accruing	0		0
Nonaccrual	477		524
Total	$ 477		$ 524

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

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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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