Loans and Allowance for Loan Losses (Past Due Status) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 3,429	$ 4,536
60 - 89 days past due	353	647
More than 90 days past due	18,826	21,157
Nonaccrual	20,255	25,288
Total past due and nonaccrual	42,863	51,628
Current and accruing	1,353,048	1,306,160
Loans held for investment	1,395,911	1,357,788	[1]
Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	115,633	113,413
Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	82,725	78,327
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	676,109	667,602
Real estate - mortgage, commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	438,105	426,328
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans held for investment	83,339	72,118
PC [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	2,528	3,668
60 - 89 days past due	353	513
More than 90 days past due	0	5
Nonaccrual	20,255	25,288
Total past due and nonaccrual	23,136	29,474
Current and accruing	1,263,513	1,205,472
Loans held for investment	1,286,649	1,234,946
PC [Member] | Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	357	0
60 - 89 days past due	0	0
More than 90 days past due	0	0
Nonaccrual	515	608
Total past due and nonaccrual	872	608
Current and accruing	107,920	105,269
Loans held for investment	108,792	105,877
PC [Member] | Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	100
60 - 89 days past due	211	0
More than 90 days past due	0	0
Nonaccrual	1,022	2,307
Total past due and nonaccrual	1,233	2,407
Current and accruing	72,837	66,723
Loans held for investment	74,070	69,130
PC [Member] | Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	1,491	2,719
60 - 89 days past due	26	147
More than 90 days past due	0	0
Nonaccrual	8,856	8,637
Total past due and nonaccrual	10,373	11,503
Current and accruing	649,407	638,364
Loans held for investment	659,780	649,867
PC [Member] | Real estate - mortgage, commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	105
60 - 89 days past due	0	141
More than 90 days past due	0	0
Nonaccrual	9,410	13,381
Total past due and nonaccrual	9,410	13,627
Current and accruing	352,209	325,356
Loans held for investment	361,619	338,983
PC [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	680	744
60 - 89 days past due	116	225
More than 90 days past due	0	5
Nonaccrual	452	355
Total past due and nonaccrual	1,248	1,329
Current and accruing	81,140	69,760
Loans held for investment	82,388	71,089
PI [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	901	868
60 - 89 days past due	0	134
More than 90 days past due	18,826	21,152
Nonaccrual	0	0
Total past due and nonaccrual	19,727	22,154
Current and accruing	89,535	100,688
Loans held for investment	109,262	122,842
PI [Member] | Commercial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	14	0
60 - 89 days past due	0	0
More than 90 days past due	2,178	2,232
Nonaccrual	0	0
Total past due and nonaccrual	2,192	2,232
Current and accruing	4,649	5,303
Loans held for investment	6,841	7,535
PI [Member] | Real estate - construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	0
More than 90 days past due	1,618	3,737
Nonaccrual	0	0
Total past due and nonaccrual	1,618	3,737
Current and accruing	7,037	5,460
Loans held for investment	8,655	9,197
PI [Member] | Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	481	579
60 - 89 days past due	0	15
More than 90 days past due	1,966	2,209
Nonaccrual	0	0
Total past due and nonaccrual	2,447	2,803
Current and accruing	13,882	14,934
Loans held for investment	16,329	17,737
PI [Member] | Real estate - mortgage, commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	404	287
60 - 89 days past due	0	119
More than 90 days past due	13,055	12,964
Nonaccrual	0	0
Total past due and nonaccrual	13,459	13,370
Current and accruing	63,030	73,975
Loans held for investment	76,489	87,345
PI [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	2	2
60 - 89 days past due	0	0
More than 90 days past due	9	10
Nonaccrual	0	0
Total past due and nonaccrual	11	12
Current and accruing	937	1,016
Loans held for investment	$ 948	$ 1,028

[1] Derived from audited consolidated financial statements