Investments (Aggregate Carrying And Approximate Market Values Of Available-For-Sale Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	$ 734,378	$ 551,103
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	3,153	7,211
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	14,277	7,925
Securities available-for-sale	723,254	550,389
U.S. Government agencies
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	5,713	2
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	20	0
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	0	0
Securities available-for-sale	5,733	2
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	128,089	94,552
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	1,033	2,051
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	1,052	407
Securities available-for-sale	128,070	96,196
U.S. Government agencies
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	561,799	425,559
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	1,950	1,093
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	12,991	7,305
Securities available-for-sale	550,758	419,347
Private label
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	11,948	649
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	95	3
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	0	0
Securities available-for-sale	12,043	652
Trust preferred securities
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	4,774	4,764
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	25	26
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	0	54
Securities available-for-sale	4,799	4,736
Corporate securities
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	16,795	21,916
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	30	475
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	167	123
Securities available-for-sale	16,658	22,268
Debt Securities
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	729,118	547,442
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	3,153	3,648
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	14,210	7,889
Securities available-for-sale	718,061	543,201
Equity Securities
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost		2,136
Available-for-sale debt securities, accumulated gross unrealized gain, before tax		3,563
Available-for-sale debt securities, accumulated gross unrealized loss, before tax		0
Securities available-for-sale		5,699
Certificates of Deposit
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	3,735
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	0
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	0
Securities available-for-sale	3,735
Investment funds
Debt Securities, Available-for-sale [Line Items]
Securities available-for-sale, amortized cost	1,525	1,525
Available-for-sale debt securities, accumulated gross unrealized gain, before tax	0	0
Available-for-sale debt securities, accumulated gross unrealized loss, before tax	67	36
Securities available-for-sale	$ 1,458	$ 1,489