Investments (Aggregate Carrying And Approximate Market Values Of Held-To-Maturity Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Securities Held-to-Maturity, Amortized Cost	$ 66,989	$ 75,169
Securities held-to-maturity, Accumulated Unrecognized Holding Gain	1,489	1,346
Securities held-to-maturity, Accumulated Unrecognized Holding Loss	0	70
Securities held-to-maturity, Estimated Fair Value	68,478	76,445
Other investment securities, at Cost	15,988	14,352
Other investment securities, Fair Value	15,988	14,352
U.S. Government Agencies Mortgage-backed Securities
Schedule of Held-to-maturity Securities [Line Items]
Securities Held-to-Maturity, Amortized Cost	62,989	71,169
Securities held-to-maturity, Accumulated Unrecognized Holding Gain	1,489	1,346
Securities held-to-maturity, Accumulated Unrecognized Holding Loss	0	70
Securities held-to-maturity, Estimated Fair Value	64,478	72,445
Trust Preferred Securities
Schedule of Held-to-maturity Securities [Line Items]
Securities Held-to-Maturity, Amortized Cost	4,000	4,000
Securities held-to-maturity, Accumulated Unrecognized Holding Gain	0	0
Securities held-to-maturity, Accumulated Unrecognized Holding Loss	0	0
Securities held-to-maturity, Estimated Fair Value	4,000	4,000
Non-Marketable Equity Securities
Schedule of Held-to-maturity Securities [Line Items]
Other investment securities, at Cost	15,988	14,352
Other investment securities, Fair Value	$ 15,988	$ 14,352