Loan Portfolio, Impaired Receivables (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Recorded Investment [Abstract]
With no related allowance recorded	$ 10,065	$ 10,149
With an allowance recorded	15,298	16,646
Total	25,363	26,795
Unpaid Principal Balance [Abstract]
With no related allowance recorded	11,158	11,162
With an allowance recorded	15,885	18,552
Total	27,043	29,714
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	4,304	4,303
Total	4,304	4,303
Average Recorded Investment [Abstract]
With no related allowance recorded	10,261	11,320
With an allowance recorded	15,376	17,694
Total	25,637	29,014
Interest Income Recognized [Abstract]
With no related allowance recorded	137	141
With an allowance recorded	152	152
Total	289	293
Real Estate Loans Construction [Member]
Recorded Investment [Abstract]
With no related allowance recorded	1,812	1,819
With an allowance recorded	1,084	1,150
Unpaid Principal Balance [Abstract]
With no related allowance recorded	2,445	2,370
With an allowance recorded	1,114	2,250
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	484	166
Average Recorded Investment [Abstract]
With no related allowance recorded	1,898	2,543
With an allowance recorded	1,099	1,685
Interest Income Recognized [Abstract]
With no related allowance recorded	7	0
With an allowance recorded	0	0
Real Estate Loans Secured by Farmland [Member]
Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Unpaid Principal Balance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Average Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	0	0
Interest Income Recognized [Abstract]
With no related allowance recorded	0
With an allowance recorded	0
Real Estate Loans Secured by 1 - 4 Family Residential [Member]
Recorded Investment [Abstract]
With no related allowance recorded	3,798	3,248
With an allowance recorded	6,379	7,544
Unpaid Principal Balance [Abstract]
With no related allowance recorded	4,215	3,667
With an allowance recorded	6,914	8,203
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	2,035	2,724
Average Recorded Investment [Abstract]
With no related allowance recorded	3,888	3,712
With an allowance recorded	6,407	7,842
Interest Income Recognized [Abstract]
With no related allowance recorded	37	50
With an allowance recorded	51	65
Other Real Estate Loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	2,509	3,135
With an allowance recorded	6,915	7,505
Unpaid Principal Balance [Abstract]
With no related allowance recorded	2,552	3,178
With an allowance recorded	6,915	7,605
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	964	1,045
Average Recorded Investment [Abstract]
With no related allowance recorded	2,529	3,141
With an allowance recorded	6,940	7,691
Interest Income Recognized [Abstract]
With no related allowance recorded	93	91
With an allowance recorded	71	73
Commercial Loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	1,946	1,947
With an allowance recorded	890	417
Unpaid Principal Balance [Abstract]
With no related allowance recorded	1,946	1,947
With an allowance recorded	912	464
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	791	338
Average Recorded Investment [Abstract]
With no related allowance recorded	1,946	1,924
With an allowance recorded	900	446
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	30	14
Consumer Loans [Member]
Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	30	30
Unpaid Principal Balance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	30	30
Related Allowance [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	30	30
Average Recorded Investment [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	30	30
Interest Income Recognized [Abstract]
With no related allowance recorded	0	0
With an allowance recorded	$ 0	$ 0

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+ 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=7512638&loc=d3e5212-111524

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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-Paragraph 14A

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