Loans and Allowance for Loan Losses (Allowance for Loan Losses, by Segment Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	$ 23,975	$ 25,085	$ 26,785	$ 29,314
Charge-offs	(1,970)	(1,724)	(5,980)	(10,836)
Recoveries	1,199	2,376	4,768	8,206
Provision (recovery of provision)	(1,679)	(350)	(4,048)	(1,297)
Balance, end of period	21,525	25,387	21,525	25,387
Commercial and agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	3,508	2,192	2,931	3,238
Charge-offs	(301)	(2)	(1,311)	(1,196)
Recoveries	171	465	825	1,376
Provision (recovery of provision)	(58)	(45)	875	(808)
Balance, end of period	3,320	2,610	3,320	2,610
Real estate - construction [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	4,778	5,652	5,233	4,987
Charge-offs	(52)	(36)	(676)	(964)
Recoveries	131	1,039	1,458	2,106
Provision (recovery of provision)	(1,089)	(1,560)	(2,247)	(1,034)
Balance, end of period	3,768	5,095	3,768	5,095
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	7,410	7,400	8,869	8,701
Charge-offs	(234)	(394)	(869)	(3,563)
Recoveries	396	285	894	962
Provision (recovery of provision)	(1,217)	1,493	(2,539)	2,684
Balance, end of period	6,355	8,784	6,355	8,784
Real estate - mortgage, commercial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	5,666	7,387	7,195	9,627
Charge-offs	(511)	(592)	(1,307)	(2,853)
Recoveries	123	357	716	2,363
Provision (recovery of provision)	(150)	(677)	(1,476)	(2,662)
Balance, end of period	5,128	6,475	5,128	6,475
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	2,613	2,454	2,557	2,761
Charge-offs	(872)	(700)	(1,817)	(2,260)
Recoveries	378	230	875	1,399
Provision (recovery of provision)	835	439	1,339	523
Balance, end of period	$ 2,954	$ 2,423	$ 2,954	$ 2,423