Loans (Past Due Status) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 10,049	$ 11,443
60 - 89 days past due	3,246	5,795
More than 90 days past due	20,453	24,060
Nonaccrual	70,503	79,242
Total past due and nonaccrual	104,251	120,540
Current and accruing	1,009,514	1,056,495
Loans held for investment	1,113,765	1,177,035	[1]
Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	77,490	79,704
Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	57,653	58,414
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	520,808	553,538
Real estate - mortgage, commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	414,995	441,836
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	42,819	43,543
PC [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	4,258	7,355
60 - 89 days past due	242	999
More than 90 days past due	55	227
Nonaccrual	70,503	79,242
Total past due and nonaccrual	75,058	87,823
Current and accruing	832,823	860,820
Loans held for investment	907,881	948,643
PC [Member] | Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	30	515
60 - 89 days past due	1	0
More than 90 days past due	0	50
Nonaccrual	2,350	2,746
Total past due and nonaccrual	2,381	3,311
Current and accruing	62,200	61,727
Loans held for investment	64,581	65,038
PC [Member] | Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	367	26
60 - 89 days past due	0	119
More than 90 days past due	0	0
Nonaccrual	11,762	14,297
Total past due and nonaccrual	12,129	14,442
Current and accruing	43,191	41,290
Loans held for investment	55,320	55,732
PC [Member] | Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	2,722	6,173
60 - 89 days past due	82	880
More than 90 days past due	55	0
Nonaccrual	19,111	18,372
Total past due and nonaccrual	21,970	25,425
Current and accruing	462,224	488,898
Loans held for investment	484,194	514,323
PC [Member] | Real estate - mortgage, commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	931	617
60 - 89 days past due	147	0
More than 90 days past due	0	177
Nonaccrual	37,217	43,621
Total past due and nonaccrual	38,295	44,415
Current and accruing	224,247	226,948
Loans held for investment	262,542	271,363
PC [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	208	24
60 - 89 days past due	12	0
More than 90 days past due	0	0
Nonaccrual	63	206
Total past due and nonaccrual	283	230
Current and accruing	40,961	41,957
Loans held for investment	41,244	42,187
PI [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	5,791	4,088
60 - 89 days past due	3,004	4,796
More than 90 days past due	20,398	23,833
Nonaccrual	0	0
Total past due and nonaccrual	29,193	32,717
Current and accruing	176,691	195,675
Loans held for investment	205,884	228,392
PI [Member] | Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	1,056	100
60 - 89 days past due	60	1
More than 90 days past due	811	1,103
Nonaccrual	0	0
Total past due and nonaccrual	1,927	1,204
Current and accruing	10,982	13,462
Loans held for investment	12,909	14,666
PI [Member] | Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	117
60 - 89 days past due	48	0
More than 90 days past due	523	655
Nonaccrual	0	0
Total past due and nonaccrual	571	772
Current and accruing	1,761	1,910
Loans held for investment	2,332	2,682
PI [Member] | Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	896	1,308
60 - 89 days past due	0	495
More than 90 days past due	3,530	4,678
Nonaccrual	0	0
Total past due and nonaccrual	4,426	6,481
Current and accruing	32,481	32,734
Loans held for investment	36,907	39,215
PI [Member] | Real estate - mortgage, commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	3,836	2,559
60 - 89 days past due	2,896	4,300
More than 90 days past due	15,533	17,384
Nonaccrual	0	0
Total past due and nonaccrual	22,265	24,243
Current and accruing	130,168	146,230
Loans held for investment	152,433	170,473
PI [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	3	4
60 - 89 days past due	0	0
More than 90 days past due	1	13
Nonaccrual	0	0
Total past due and nonaccrual	4	17
Current and accruing	1,299	1,339
Loans held for investment	$ 1,303	$ 1,356

[1] Derived from audited consolidated financial statements