Investments (Aggregate Carrying And Approximate Market Values Of Held-To-Maturity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	$ 64,449	$ 75,169
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	1,222	1,346
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	25	70
Securities held-to-maturity, Estimated Fair Value	65,646	76,445
US Government Agencies Debt Securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	60,449	71,169
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	1,222	1,346
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	25	70
Securities held-to-maturity, Estimated Fair Value	61,646	72,445
Trust preferred securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	4,000	4,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	0	0
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Securities held-to-maturity, Estimated Fair Value	4,000	4,000
Securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity, Amortized Cost	14,147	14,352
Securities held-to-maturity, Estimated Fair Value	$ 14,147	$ 14,352