Investment Securities (Scheduled Maturities Of Securities Available For Sale And Securities Held To Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment Securities [Abstract]
Debt securities available for sale, Due in one year or less, Amortized Cost	$ 2
Debt securities available for sale, Due from one to five years, Amortized Cost	123,010
Debt securities available for sale, Due after five years through ten years, Amortized Cost	294,812
Debt securities available for sale, Due after ten years, Amortized Cost	110,634
Debt securities available for sale, Amortized Cost	528,458
Debt securities available for sale, Due in one year or less, Fair Value	2
Debt securities available for sale, Due from one to five years, Fair Value	122,228
Debt securities available for sale, Due after five years through ten years, Fair Value	292,544
Debt securities available for sale, Due after ten years, Fair Value	110,199
Debt securities available for sale, Fair Value	524,973
Debt securities held to maturity, Due in one year or less, Amortized Cost	57,692
Debt securities held to maturity, Due from one to five years, Amortized Cost	159,758
Debt securities held to maturity, Due after five years through ten years, Amortized Cost	103,593
Debt securities held to maturity, Due after ten years, Amortized Cost	195,423
Securities held to maturity, Amortized Cost	516,466	$ 543,338
Debt securities held to maturity, Due in one year or less, Fair Value	57,757
Debt securities held to maturity, Due from one to five years, Fair Value	161,514
Debt securities held to maturity, Due after five years through ten years, Fair Value	102,507
Debt securities held to maturity, Due after ten years, Fair Value	191,205
Securities held to maturity, Fair Value	$ 512,983	$ 539,991