Loans (Summary of Impaired Loans by Classes of Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	$ 27,511	$ 44,383
Unpaid Principal Balance	27,516	45,151
Related Valuation Allowance	3,399	6,389
Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	169,504	97,815
Unpaid Principal Balance	272,336	122,367
Related Valuation Allowance	0	0
Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	197,015	142,198
Unpaid Principal Balance	299,852	167,518
Related Valuation Allowance	3,399	6,389
Commercial [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	4,906	18,898
Unpaid Principal Balance	4,911	19,426
Related Valuation Allowance	2,729	5,700
Commercial [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	53,542	31,039
Unpaid Principal Balance	78,494	37,703
Related Valuation Allowance	0	0
Commercial [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	58,448	49,937
Unpaid Principal Balance	83,405	57,129
Related Valuation Allowance	2,729	5,700
Commercial real estate [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	2,741	4,448
Unpaid Principal Balance	2,741	4,688
Related Valuation Allowance	516	497
Commercial real estate [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	69,713	53,518
Unpaid Principal Balance	118,751	69,130
Related Valuation Allowance	0	0
Commercial real estate [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	72,454	57,966
Unpaid Principal Balance	121,492	73,818
Related Valuation Allowance	516	497
Real estate construction and land development [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	3,362	2,136
Unpaid Principal Balance	8,894	3,108
Related Valuation Allowance	0	0
Real estate construction and land development [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	3,362	2,136
Unpaid Principal Balance	8,894	3,108
Related Valuation Allowance	0	0
Residential mortgage [Member] | Impaired loans with a valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	19,864	21,037
Unpaid Principal Balance	19,864	21,037
Related Valuation Allowance	154	192
Residential mortgage [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	34,310	7,638
Unpaid Principal Balance	54,414	8,644
Related Valuation Allowance	0	0
Residential mortgage [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	54,174	28,675
Unpaid Principal Balance	74,278	29,681
Related Valuation Allowance	154	192
Consumer installment [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	1,004	498
Unpaid Principal Balance	1,538	512
Related Valuation Allowance	0	0
Consumer installment [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	1,004	498
Unpaid Principal Balance	1,538	512
Related Valuation Allowance	0	0
Home equity [Member] | Impaired loans with no valuation allowance [Member]
Schedule of Impaired loans by classes
Recorded Investment	7,573	2,986
Unpaid Principal Balance	10,245	3,270
Related Valuation Allowance	0	0
Home equity [Member] | Total Impaired Loans [Member]
Schedule of Impaired loans by classes
Recorded Investment	7,573	2,986
Unpaid Principal Balance	10,245	3,270
Related Valuation Allowance	$ 0	$ 0