Loans (Summary of Information Related to Impaired Loans) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	$ 136,772	$ 131,534
Interest income recognized related to loans with impaired status	1,194	1,180
Commercial [Member]
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	45,017	38,576
Interest income recognized related to loans with impaired status	329	289
Real estate commercial [Member]
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	57,956	60,240
Interest income recognized related to loans with impaired status	458	525
Real estate construction [Member]
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	2,068	2,515
Interest income recognized related to loans with impaired status	25	27
Real estate residential [Member]
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	28,092	27,352
Interest income recognized related to loans with impaired status	366	331
Consumer installment [Member]
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	387	499
Interest income recognized related to loans with impaired status	1	0
Home equity [Member]
Schedule representing information related to impaired loans
Average recorded investment related to impaired loans	3,252	2,352
Interest income recognized related to loans with impaired status	$ 15	$ 8