Investment Securities (Investments Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	$ 129,206	$ 251
Securities available for sale, Less than 12 months, Unrealized Losses	1,367	1
Securities available for sale, 12 months or longer, Fair Value	16,613	438,290
Securities available for sale, 12 months or longer, Unrealized Losses	264	10,749
Securities available for sale, Fair Value, Total	145,819	438,541
Securities available for sale, Unrealized Losses, Total	1,631	10,750
Securities held to maturity, Less than 12 months, Fair Value	49,517	50,519
Securities held to maturity, Less than 12 months, Unrealized Losses	228	181
Securities held to maturity, 12 months or longer, Fair Value	30,589	234,507
Securities held to maturity, 12 months or longer, Unrealized Losses	395	7,718
Securities held to maturity, Fair Value, Total	80,106	285,026
Securities held to maturity, Unrealized Losses, Total	623	7,899
Total Securities, Less than 12 months, Fair Value	178,723	50,770
Total Securities, Less than 12 months, Unrealized Losses	1,595	182
Total Securities, 12 months or longer, Fair Value	47,202	672,797
Total Securities, 12 months or longer, Unrealized Losses	659	18,467
Total Securities, Fair Value	225,925	723,567
Total Securities, Unrealized Losses	2,254	18,649
U.S. Government Agencies And Government Sponsored Enterprises [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, 12 months or longer, Fair Value		152,028
Securities available for sale, 12 months or longer, Unrealized Losses		3,074
Securities available for sale, Fair Value, Total		152,028
Securities available for sale, Unrealized Losses, Total		3,074
State And Political Subdivisions [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Less than 12 months, Fair Value		35,751
Securities held to maturity, Less than 12 months, Unrealized Losses		91
Securities held to maturity, 12 months or longer, Fair Value		49,534
Securities held to maturity, 12 months or longer, Unrealized Losses		1,120
Securities held to maturity, Fair Value, Total		85,285
Securities held to maturity, Unrealized Losses, Total		1,211
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	8,803
Securities available for sale, Less than 12 months, Unrealized Losses	57
Securities available for sale, 12 months or longer, Fair Value	8	56
Securities available for sale, Fair Value, Total	8,811	56
Securities available for sale, Unrealized Losses, Total	57
Securities held to maturity, Less than 12 months, Fair Value	9,120
Securities held to maturity, Less than 12 months, Unrealized Losses	40
Securities held to maturity, 12 months or longer, Fair Value	13,486	57,973
Securities held to maturity, 12 months or longer, Unrealized Losses	216	2,179
Securities held to maturity, Fair Value, Total	22,606	57,973
Securities held to maturity, Unrealized Losses, Total	256	2,179
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	4,889
Securities available for sale, Less than 12 months, Unrealized Losses	18
Securities available for sale, 12 months or longer, Fair Value		6
Securities available for sale, Fair Value, Total	4,889	6
Securities available for sale, Unrealized Losses, Total	18
Securities held to maturity, Less than 12 months, Fair Value	15,127
Securities held to maturity, Less than 12 months, Unrealized Losses	30
Securities held to maturity, 12 months or longer, Fair Value	7,988	75,603
Securities held to maturity, 12 months or longer, Unrealized Losses	73	2,597
Securities held to maturity, Fair Value, Total	23,115	75,603
Securities held to maturity, Unrealized Losses, Total	103	2,597
Collateralized Mortgage Obligations [Member] \| Government National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Less than 12 months, Fair Value	8,760
Securities held to maturity, Less than 12 months, Unrealized Losses	72
Securities held to maturity, 12 months or longer, Fair Value	892	17,263
Securities held to maturity, 12 months or longer, Unrealized Losses	11	535
Securities held to maturity, Fair Value, Total	9,652	17,263
Securities held to maturity, Unrealized Losses, Total	83	535
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	129,206	251
Securities available for sale, Less than 12 months, Unrealized Losses	1,367	1
Securities available for sale, 12 months or longer, Fair Value	16,613	286,262
Securities available for sale, 12 months or longer, Unrealized Losses	264	7,675
Securities available for sale, Fair Value, Total	145,819	286,513
Securities available for sale, Unrealized Losses, Total	1,631	7,676
Securities held to maturity, Less than 12 months, Fair Value	49,517	14,768
Securities held to maturity, Less than 12 months, Unrealized Losses	228	90
Securities held to maturity, 12 months or longer, Fair Value	30,589	184,973
Securities held to maturity, 12 months or longer, Unrealized Losses	395	6,598
Securities held to maturity, Fair Value, Total	80,106	199,741
Securities held to maturity, Unrealized Losses, Total	623	6,688
Mortgage-Backed Securities [Member] \| Federal National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	104,634	251
Securities available for sale, Less than 12 months, Unrealized Losses	1,277	1
Securities available for sale, 12 months or longer, Fair Value	7,196	247,615
Securities available for sale, 12 months or longer, Unrealized Losses	103	6,324
Securities available for sale, Fair Value, Total	111,830	247,866
Securities available for sale, Unrealized Losses, Total	1,380	6,325
Securities held to maturity, Less than 12 months, Fair Value	2,388	1,518
Securities held to maturity, Less than 12 months, Unrealized Losses	6	3
Securities held to maturity, 12 months or longer, Fair Value		8,695
Securities held to maturity, 12 months or longer, Unrealized Losses		258
Securities held to maturity, Fair Value, Total	2,388	10,213
Securities held to maturity, Unrealized Losses, Total	6	261
Mortgage-Backed Securities [Member] \| Federal Home Loan Mortgage Corporation [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	10,347
Securities available for sale, Less than 12 months, Unrealized Losses	11
Securities available for sale, 12 months or longer, Fair Value	9,409	33,918
Securities available for sale, 12 months or longer, Unrealized Losses	161	1,275
Securities available for sale, Fair Value, Total	19,756	33,918
Securities available for sale, Unrealized Losses, Total	172	1,275
Securities held to maturity, Less than 12 months, Fair Value	2,967	1,467
Securities held to maturity, Less than 12 months, Unrealized Losses	19	5
Securities held to maturity, 12 months or longer, Fair Value	2,598	2,923
Securities held to maturity, 12 months or longer, Unrealized Losses	28	188
Securities held to maturity, Fair Value, Total	5,565	4,390
Securities held to maturity, Unrealized Losses, Total	47	193
Mortgage-Backed Securities [Member] \| Government National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Less than 12 months, Fair Value	533
Securities available for sale, Less than 12 months, Unrealized Losses	4
Securities available for sale, 12 months or longer, Fair Value		4,667
Securities available for sale, 12 months or longer, Unrealized Losses		76
Securities available for sale, Fair Value, Total	533	4,667
Securities available for sale, Unrealized Losses, Total	4	76
Securities held to maturity, Less than 12 months, Fair Value	11,155	11,783
Securities held to maturity, Less than 12 months, Unrealized Losses	61	82
Securities held to maturity, 12 months or longer, Fair Value	5,625	22,516
Securities held to maturity, 12 months or longer, Unrealized Losses	67	841
Securities held to maturity, Fair Value, Total	16,780	34,299
Securities held to maturity, Unrealized Losses, Total	$ 128	$ 923

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