Loans and Allowance for Loan Losses (Nonaccrual Status) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	$ 18,016	$ 25,288
Net loans held for investment	1,528,600	1,337,443
Nonperforming [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	18,016	25,288
Loans more than 90 days delinquent, still on accrual	817	5
Net loans held for investment	18,833	25,293
Nonperforming [Member] \| Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	1,053	608
Nonperforming [Member] \| Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	110	2,307
Nonperforming [Member] \| Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	9,106	8,637
Nonperforming [Member] \| Real estate - mortgage, Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	7,209	13,381
Nonperforming [Member] \| Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	$ 538	$ 355

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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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- Definition

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

+ References

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- Definition

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+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Reference 2: 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)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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