Loans (Summary of Impaired Loans by Classes of Loans) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	$ 25,100	$ 23,234	$ 27,198
Unpaid Principal Balance	25,375	23,648	27,526
Related Valuation Allowance	1,912	1,338	2,065
Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	104,052	111,433	101,297
Unpaid Principal Balance	133,493	141,622	122,701
Related Valuation Allowance	0	0	0
Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	129,152	134,667	128,495
Unpaid Principal Balance	158,868	165,270	150,227
Related Valuation Allowance	1,912	1,338	2,065
Commercial [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	3,433	966	3,534
Unpaid Principal Balance	3,527	1,040	3,704
Related Valuation Allowance	1,119	293	1,250
Commercial [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	33,733	38,094	38,150
Unpaid Principal Balance	39,382	44,557	42,914
Related Valuation Allowance	0	0	0
Commercial [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	37,166	39,060	41,684
Unpaid Principal Balance	42,909	45,597	46,618
Related Valuation Allowance	1,119	293	1,250
Real estate commercial [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	1,780	2,587	3,720
Unpaid Principal Balance	1,961	2,927	3,878
Related Valuation Allowance	496	710	371
Real estate commercial [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	57,628	60,616	49,074
Unpaid Principal Balance	79,696	82,693	62,207
Related Valuation Allowance	0	0	0
Real estate commercial [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	59,408	63,203	52,794
Unpaid Principal Balance	81,657	85,620	66,085
Related Valuation Allowance	496	710	371
Real estate construction [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	0	0	0
Unpaid Principal Balance	0	0	0
Related Valuation Allowance	0	0	0
Real estate construction [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	663	162	160
Unpaid Principal Balance	836	255	366
Related Valuation Allowance	0	0	0
Real estate construction [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	663	162	160
Unpaid Principal Balance	836	255	366
Related Valuation Allowance	0	0	0
Land development [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	0	0	0
Unpaid Principal Balance	0	0	0
Related Valuation Allowance	0	0	0
Land development [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	1,877	1,928	4,472
Unpaid Principal Balance	3,428	3,484	7,773
Related Valuation Allowance	0	0	0
Land development [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	1,877	1,928	4,472
Unpaid Principal Balance	3,428	3,484	7,773
Related Valuation Allowance	0	0	0
Real estate residential [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	19,887	19,681	19,944
Unpaid Principal Balance	19,887	19,681	19,944
Related Valuation Allowance	297	335	444
Real estate residential [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	7,382	7,994	6,589
Unpaid Principal Balance	7,382	7,994	6,589
Related Valuation Allowance	0	0	0
Real estate residential [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	27,269	27,675	26,533
Unpaid Principal Balance	27,269	27,675	26,533
Related Valuation Allowance	297	335	444
Consumer installment [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	444	518	806
Unpaid Principal Balance	444	518	806
Related Valuation Allowance	0	0	0
Consumer installment [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	444	518	806
Unpaid Principal Balance	444	518	806
Related Valuation Allowance	0	0	0
Home equity [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	2,325	2,121	2,046
Unpaid Principal Balance	2,325	2,121	2,046
Related Valuation Allowance	0	0	0
Home equity [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	2,325	2,121	2,046
Unpaid Principal Balance	2,325	2,121	2,046
Related Valuation Allowance	$ 0	$ 0	$ 0