The balance of financing receivables that were collectively evaluated for impairment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

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The balance of financing receivables that were individually evaluated for impairment.

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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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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-SubTopic 10

-Section 50

-Paragraph 4

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-Paragraph 2

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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-Topic 942

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-Section S99

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-Subparagraph (SX 210.9-03.7)

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Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Loan Portfolio [Abstract]
Total LHFI	$ 6,449,469	$ 5,798,881
Less Allowance For Loan Losses, LHFI	69,616	66,448	78,738	89,518
Net LHFI	6,379,853	5,732,433
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	79,343	65,238
LHFI, Collectively Evaluated For Impairment	6,370,126	5,733,643
Total LHFI	6,449,469	5,798,881
Loans Secured by Real Estate [Member] \| Construction, Land Development and Other Land [Member]
Loan Portfolio [Abstract]
Total LHFI	619,877	596,889
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	13,867	13,327
LHFI, Collectively Evaluated For Impairment	606,010	583,562
Total LHFI	619,877	596,889
Loans Secured by Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Loan Portfolio [Abstract]
Total LHFI	1,634,397	1,485,564
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	25,621	21,603
LHFI, Collectively Evaluated For Impairment	1,608,776	1,463,961
Total LHFI	1,634,397	1,485,564
Loans Secured by Real Estate [Member] \| Nonfarm, Nonresidential Properties [Member]
Loan Portfolio [Abstract]
Total LHFI	1,553,193	1,415,139
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	25,717	21,809
LHFI, Collectively Evaluated For Impairment	1,527,476	1,393,330
Total LHFI	1,553,193	1,415,139
Loans Secured by Real Estate [Member] \| Other Real Estate Properties [Member]
Loan Portfolio [Abstract]
Total LHFI	253,787	189,362
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	1,318	1,327
LHFI, Collectively Evaluated For Impairment	252,469	188,035
Total LHFI	253,787	189,362
Commercial and Industrial Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	1,270,350	1,157,614
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	12,104	6,286
LHFI, Collectively Evaluated For Impairment	1,258,246	1,151,328
Total LHFI	1,270,350	1,157,614
Consumer Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	167,964	165,308
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	88	151
LHFI, Collectively Evaluated For Impairment	167,876	165,157
Total LHFI	167,964	165,308
Other Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	949,901	789,005
Loans and Leases Receivable, Other Information [Abstract]
LHFI, Individually Evaluated For Impairment	628	735
LHFI, Collectively Evaluated For Impairment	949,273	788,270
Total LHFI	$ 949,901	$ 789,005