Loans and Allowance for Loan Losses (Allowance for Loan Losses, by Segment Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	$ 17,989	$ 23,975	$ 20,345	$ 26,785
Charge-offs	(1,293)	(1,970)	(3,855)	(5,980)
Recoveries	556	1,199	2,688	4,768
Provision (recovery of provision)	(64)	(1,679)	(1,990)	(4,048)
Balance, end of period	17,188	21,525	17,188	21,525
Commercial and agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	2,712	3,508	3,915	2,931
Charge-offs	0	(301)	(306)	(1,311)
Recoveries	203	171	852	825
Provision (recovery of provision)	(251)	(58)	(1,797)	875
Balance, end of period	2,664	3,320	2,664	3,320
Real estate - construction [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	2,207	4,778	3,163	5,233
Charge-offs	(51)	(52)	(136)	(676)
Recoveries	120	131	495	1,458
Provision (recovery of provision)	(245)	(1,089)	(1,491)	(2,247)
Balance, end of period	2,031	3,768	2,031	3,768
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	5,517	7,410	5,847	8,869
Charge-offs	(393)	(234)	(769)	(869)
Recoveries	103	396	412	894
Provision (recovery of provision)	(46)	(1,217)	(309)	(2,539)
Balance, end of period	5,181	6,355	5,181	6,355
Real estate - mortgage, commercial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	3,306	5,666	4,179	7,195
Charge-offs	(33)	(511)	(301)	(1,307)
Recoveries	56	123	442	716
Provision (recovery of provision)	(194)	(150)	(1,185)	(1,476)
Balance, end of period	3,135	5,128	3,135	5,128
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	4,247	2,613	3,241	2,557
Charge-offs	(816)	(872)	(2,343)	(1,817)
Recoveries	74	378	487	875
Provision (recovery of provision)	672	835	2,792	1,339
Balance, end of period	$ 4,177	$ 2,954	$ 4,177	$ 2,954