Loans and Asset Quality Information (Details 6) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Company's nonaccrual loans:
Nonaccrual loans	$ 76,115	$ 79,155
Commercial Unsecured [Member]
Company's nonaccrual loans:
Nonaccrual loans	394	260
Commercial Secured [Member]
Company's nonaccrual loans:
Nonaccrual loans	4,148	2,776
Secured by Inventory and Accounts Receivable [Member]
Company's nonaccrual loans:
Nonaccrual loans	1,138	1,327
Real Estate construction, land development and other land loans [Member]
Company's nonaccrual loans:
Nonaccrual loans	19,576	21,557
Real estate residential, farmland and mutli-family [Member]
Company's nonaccrual loans:
Nonaccrual loans	28,491	30,158
Real estate home equity lines of credit [Member]
Company's nonaccrual loans:
Nonaccrual loans	2,646	2,535
Real estate commercial [Member]
Company's nonaccrual loans:
Nonaccrual loans	19,252	20,214
Consumer [Member]
Company's nonaccrual loans:
Nonaccrual loans	470	328
Non-covered [Member]
Company's nonaccrual loans:
Nonaccrual loans	44,129	41,938
Non-covered [Member] | Commercial Unsecured [Member]
Company's nonaccrual loans:
Nonaccrual loans	281	222
Non-covered [Member] | Commercial Secured [Member]
Company's nonaccrual loans:
Nonaccrual loans	4,037	2,662
Non-covered [Member] | Secured by Inventory and Accounts Receivable [Member]
Company's nonaccrual loans:
Nonaccrual loans	963	545
Non-covered [Member] | Real Estate construction, land development and other land loans [Member]
Company's nonaccrual loans:
Nonaccrual loans	8,550	8,055
Non-covered [Member] | Real estate residential, farmland and mutli-family [Member]
Company's nonaccrual loans:
Nonaccrual loans	18,648	17,814
Non-covered [Member] | Real estate home equity lines of credit [Member]
Company's nonaccrual loans:
Nonaccrual loans	2,295	2,200
Non-covered [Member] | Real estate commercial [Member]
Company's nonaccrual loans:
Nonaccrual loans	8,885	10,115
Non-covered [Member] | Consumer [Member]
Company's nonaccrual loans:
Nonaccrual loans	470	325
Covered [Member]
Company's nonaccrual loans:
Nonaccrual loans	31,986	37,217
Covered [Member] | Commercial Unsecured [Member]
Company's nonaccrual loans:
Nonaccrual loans	113	38
Covered [Member] | Commercial Secured [Member]
Company's nonaccrual loans:
Nonaccrual loans	111	114
Covered [Member] | Secured by Inventory and Accounts Receivable [Member]
Company's nonaccrual loans:
Nonaccrual loans	175	782
Covered [Member] | Real Estate construction, land development and other land loans [Member]
Company's nonaccrual loans:
Nonaccrual loans	11,026	13,502
Covered [Member] | Real estate residential, farmland and mutli-family [Member]
Company's nonaccrual loans:
Nonaccrual loans	9,843	12,344
Covered [Member] | Real estate home equity lines of credit [Member]
Company's nonaccrual loans:
Nonaccrual loans	351	335
Covered [Member] | Real estate commercial [Member]
Company's nonaccrual loans:
Nonaccrual loans	10,367	10,099
Covered [Member] | Consumer [Member]
Company's nonaccrual loans:
Nonaccrual loans		$ 3