Investment Securities (Amortized Cost And Fair Value Of Investment Securities By Contractual Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available-for-sale, Amortized cost [Abstract]
Due before one year	$ 71,697
Due after one year through five years	204,707
Due after five years through ten years	338,966
Due after ten years	456,216
Total	1,071,586
Available-for-sale, Fair value [Abstract]
Due before one year	71,786
Due after one year through five years	204,012
Due after five years through ten years	338,005
Due after ten years	456,295
Fair value	1,070,098	$ 1,493,639
Held-to-maturity, Amortized cost [Abstract]
Due after one year through five years	7,016
Due after ten years	86,574
Held-to-maturity Securities, Total	93,590	93,765
Held-to-maturity, Fair value [Abstract]
Due after one year through five years	7,490
Due after ten years	84,109
Fair value	$ 91,599	$ 91,914