Investments (Amortized Cost And Estimated Fair Value Of Debt Securities By Contractual Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Securities Available-for-Sale, Amortized Cost
Securities Available-for-Sale, Due in one year or less, Cost	$ 3,640
Securities Available-for-Sale, Due after one year through five years, Cost	25,215
Securities Available-for-Sale, Due after five years through ten years, Cost	59,193
Securities Available-for-Sale, Due after ten years, Cost	333,385
Securities Available-for-Sale, Cost, Total	421,433
Securities Available-for-Sale, Estimated Fair Value
Securities Available-for-Sale, Due in one year or less, Estimated Fair Value	3,662
Securities Available-for-Sale, Due after one year through five years, Estimated Fair Value	17,395
Securities Available-for-Sale, Due after five years through ten years, Estimated Fair Value	68,514
Securities Available-for-Sale, Due after ten years, Estimated Fair Value	339,897
Securities Available-for-Sale, Estimated Fair Value, Total	429,468
Securities Held-to-Maturity, Amortized Cost
Securities Held-to-Maturity, Due in one year or less, Cost	0
Securities Held-to-Maturity, Due after one year through five years, Cost	0
Securities Held-to-Maturity, Due after five years through ten years, Cost	0
Securities Held-to-Maturity, Due after ten years, Cost	79,499
Securities Held-to-Maturity, Amortized Cost	79,499	$ 88,937
Securities Held-to-Maturity, Estimated Fair Value
Securities Held-to-Maturity, Due in one year or less, Estimated Fair Value	0
Securities Held-to-Maturity, Due after one year through five years, Estimated Fair Value	0
Securities Held-to-Maturity, Due after five years through ten years, Estimated Fair Value	0
Securities Held-to-Maturity, Due after ten years, Estimated Fair Value	82,993
Securities Held-to-Maturity, Estimated Fair Value	$ 82,993	$ 90,810