Loans and Asset Quality Information (Details 7) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013
Analysis of the payment status of loans
30-59 Days Past Due	$ 14,277	$ 26,338
60-89 Days Past Due	6,253	6,819
Nonaccrual loans	68,471	79,155
Current	2,344,733	2,349,954
Loans - non-covered	2,257,530	2,252,885	2,190,583
Unamortized net deferred loan costs	651	928	1,168
Total Covered Loans - Carrying Value	176,855	210,309	240,279
Loans	2,434,385	2,463,194	2,430,862
Commercial Unsecured [Member]
Analysis of the payment status of loans
Nonaccrual loans	115	260
Commercial Secured [Member]
Analysis of the payment status of loans
Nonaccrual loans	3,905	2,776
Secured by Inventory and Accounts Receivable [Member]
Analysis of the payment status of loans
Nonaccrual loans	338	1,327
Real estate construction, land development other land loans [Member]
Analysis of the payment status of loans
Nonaccrual loans	14,300	21,557
Real estate residential, farmland and mutli-family [Member]
Analysis of the payment status of loans
Nonaccrual loans	28,383	30,158
Loans - non-covered	867,175	869,387	850,060
Real estate home equity lines of credit [Member]
Analysis of the payment status of loans
Nonaccrual loans	2,677	2,535
Loans - non-covered	200,510	198,127	198,281
Real estate commercial [Member]
Analysis of the payment status of loans
Nonaccrual loans	18,196	20,214
Consumer [Member]
Analysis of the payment status of loans
Nonaccrual loans	557	328
Loans - non-covered	45,250	49,696	51,453
Non-covered [Member]
Analysis of the payment status of loans
30-59 Days Past Due	13,283	21,159
60-89 Days Past Due	5,228	6,051
Nonaccrual loans	47,533	41,938
Current	2,190,835	2,182,809
Loans - non-covered	2,256,879	2,251,957	2,189,415
Non-covered [Member] | Commercial Unsecured [Member]
Analysis of the payment status of loans
30-59 Days Past Due	426	347
60-89 Days Past Due	7	94
Nonaccrual loans	110	222
Current	35,534	36,352
Loans - non-covered	36,077	37,015
Non-covered [Member] | Commercial Secured [Member]
Analysis of the payment status of loans
30-59 Days Past Due	1,309	1,233
60-89 Days Past Due	310	462
Nonaccrual loans	3,628	2,662
Current	118,854	117,923
Loans - non-covered	124,101	122,280
Non-covered [Member] | Secured by Inventory and Accounts Receivable [Member]
Analysis of the payment status of loans
30-59 Days Past Due	146	438
60-89 Days Past Due	64	767
Nonaccrual loans	338	545
Current	17,944	19,426
Loans - non-covered	18,492	21,176
Non-covered [Member] | Real estate construction, land development other land loans [Member]
Analysis of the payment status of loans
30-59 Days Past Due	308	2,304
60-89 Days Past Due	605	1,391
Nonaccrual loans	9,001	8,055
Current	237,455	232,920
Loans - non-covered	247,369	244,670
Non-covered [Member] | Real estate residential, farmland and mutli-family [Member]
Analysis of the payment status of loans
30-59 Days Past Due	7,867	11,682
60-89 Days Past Due	3,523	2,631
Nonaccrual loans	21,168	17,814
Current	834,617	837,260
Loans - non-covered	867,175	869,387
Non-covered [Member] | Real estate home equity lines of credit [Member]
Analysis of the payment status of loans
30-59 Days Past Due	1,058	1,465
60-89 Days Past Due	133	305
Nonaccrual loans	2,436	2,200
Current	196,883	194,157
Loans - non-covered	200,510	198,127
Non-covered [Member] | Real estate commercial [Member]
Analysis of the payment status of loans
30-59 Days Past Due	1,758	3,196
60-89 Days Past Due	447	214
Nonaccrual loans	10,297	10,115
Current	705,403	696,081
Loans - non-covered	717,905	709,606
Non-covered [Member] | Consumer [Member]
Analysis of the payment status of loans
30-59 Days Past Due	411	494
60-89 Days Past Due	139	187
Nonaccrual loans	555	325
Current	44,145	48,690
Loans - non-covered	45,250	49,696
Covered [Member]
Analysis of the payment status of loans
30-59 Days Past Due	994	5,179
60-89 Days Past Due	1,025	768
Nonaccrual loans	20,938	37,217
Current	153,898	167,145
Total Covered Loans - Carrying Value	176,855	210,309	240,279
Covered [Member] | Commercial Unsecured [Member]
Analysis of the payment status of loans
Nonaccrual loans	5	38
Covered [Member] | Commercial Secured [Member]
Analysis of the payment status of loans
Nonaccrual loans	277	114
Covered [Member] | Secured by Inventory and Accounts Receivable [Member]
Analysis of the payment status of loans
Nonaccrual loans		782
Covered [Member] | Real estate construction, land development other land loans [Member]
Analysis of the payment status of loans
Nonaccrual loans	5,299	13,502
Covered [Member] | Real estate residential, farmland and mutli-family [Member]
Analysis of the payment status of loans
Nonaccrual loans	7,215	12,344
Covered [Member] | Real estate home equity lines of credit [Member]
Analysis of the payment status of loans
Nonaccrual loans	241	335
Covered [Member] | Real estate commercial [Member]
Analysis of the payment status of loans
Nonaccrual loans	7,899	10,099
Covered [Member] | Consumer [Member]
Analysis of the payment status of loans
Nonaccrual loans	$ 2	$ 3