Loans and Allowance for Loan Losses (Impaired Loans, Average Recorded Investment and Interest Income Recognized) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
With no related alowance recorded, average recorded investment	$ 29,238	$ 51,163	$ 71,121
With no related allowance recorded, interest income recognized	525	397	624
With an allowance recorded, average recorded investment	7,832	7,844	17,301
With an allowance recorded, interest income recognized	291	39	522
Impaired Financing Receivable, Average Recorded Investment	37,070	59,007	88,422
Impaired Financing Receivable, Interest Income, Cash Basis Method	816	436	1,146
Commercial and agricultural [Member]
Financing Receivable, Impaired [Line Items]
With no related alowance recorded, average recorded investment	0	784	1,989
With no related allowance recorded, interest income recognized	0	8	42
With an allowance recorded, average recorded investment	535	283	706
With an allowance recorded, interest income recognized	20	5	16
Impaired Financing Receivable, Average Recorded Investment	535	1,067	2,695
Impaired Financing Receivable, Interest Income, Cash Basis Method	20	13	58
Real estate - construction [Member]
Financing Receivable, Impaired [Line Items]
With no related alowance recorded, average recorded investment	2,867	9,075	15,130
With no related allowance recorded, interest income recognized	40	35	92
With an allowance recorded, average recorded investment	0	638	1,762
With an allowance recorded, interest income recognized	0	9	0
Impaired Financing Receivable, Average Recorded Investment	2,867	9,713	16,892
Impaired Financing Receivable, Interest Income, Cash Basis Method	40	44	92
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Impaired [Line Items]
With no related alowance recorded, average recorded investment	8,797	11,920	18,237
With no related allowance recorded, interest income recognized	131	100	204
With an allowance recorded, average recorded investment	3,148	2,713	1,764
With an allowance recorded, interest income recognized	75	20	61
Impaired Financing Receivable, Average Recorded Investment	11,945	14,633	20,001
Impaired Financing Receivable, Interest Income, Cash Basis Method	206	120	265
Real estate - mortgage, commercial [Member]
Financing Receivable, Impaired [Line Items]
With no related alowance recorded, average recorded investment	17,574	29,384	35,765
With no related allowance recorded, interest income recognized	354	254	286
With an allowance recorded, average recorded investment	4,149	4,127	13,069
With an allowance recorded, interest income recognized	196	4	445
Impaired Financing Receivable, Average Recorded Investment	21,723	33,511	48,834
Impaired Financing Receivable, Interest Income, Cash Basis Method	550	258	731
Consumer [Member]
Financing Receivable, Impaired [Line Items]
With no related alowance recorded, average recorded investment	0	0	0
With no related allowance recorded, interest income recognized	0	0	0
With an allowance recorded, average recorded investment	0	83	0
With an allowance recorded, interest income recognized	0	1	0
Impaired Financing Receivable, Average Recorded Investment	0	83	0
Impaired Financing Receivable, Interest Income, Cash Basis Method	$ 0	$ 1	$ 0

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5258-111524

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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