Investment Securities (Investments Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands	Sep. 30, 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	$ 74,468	$ 251
Securities available for sale, Less than 12 months, Unrealized Losses	605	1
Securities available for sale, 12 months or longer, Fair Value	40,032	438,290
Securities available for sale, 12 months or longer, Unrealized Losses	327	10,749
Securities available for sale, Fair Value, Total	114,500	438,541
Securities available for sale, Unrealized Losses, Total	932	10,750
Securities held to maturity, Less than 12 months, Fair Value	26,272	50,519
Securities held to maturity, Less than 12 months, Unrealized Losses	119	181
Securities held to maturity, 12 months or longer, Fair Value	58,860	234,507
Securities held to maturity, 12 months or longer, Unrealized Losses	642	7,718
Securities held to maturity, Fair Value, Total	85,132	285,026
Securities held to maturity, Unrealized Losses, Total	761	7,899
Total Securities, Less than 12 months, Fair Value	100,740	50,770
Total Securities, Less than 12 months, Unrealized Losses	724	182
Total Securities, 12 months or longer, Fair Value	98,892	672,797
Total Securities, 12 months or longer, Unrealized Losses	969	18,467
Total Securities, Fair Value	199,632	723,567
Total Securities, Unrealized Losses	1,693	18,649
U.S. Government Agency 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	8,986	152,028
Securities available for sale, 12 months or longer, Unrealized Losses	14	3,074
Securities available for sale, Fair Value, Total	8,986	152,028
Securities available for sale, Unrealized Losses, Total	14	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	2,011	35,751
Securities held to maturity, Less than 12 months, Unrealized Losses	5	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	2,011	85,285
Securities held to maturity, Unrealized Losses, Total	5	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	5,178
Securities available for sale, Less than 12 months, Unrealized Losses	34
Securities available for sale, 12 months or longer, Fair Value	16	56
Securities available for sale, Fair Value, Total	5,194	56
Securities available for sale, Unrealized Losses, Total	34
Securities held to maturity, Less than 12 months, Fair Value	8,207
Securities held to maturity, Less than 12 months, Unrealized Losses	35
Securities held to maturity, 12 months or longer, Fair Value	23,372	57,973
Securities held to maturity, 12 months or longer, Unrealized Losses	295	2,179
Securities held to maturity, Fair Value, Total	31,579	57,973
Securities held to maturity, Unrealized Losses, Total	330	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	4,966
Securities available for sale, Less than 12 months, Unrealized Losses	17
Securities available for sale, 12 months or longer, Fair Value		6
Securities available for sale, Fair Value, Total	4,966	6
Securities available for sale, Unrealized Losses, Total	17
Securities held to maturity, Less than 12 months, Fair Value	11,631
Securities held to maturity, Less than 12 months, Unrealized Losses	26
Securities held to maturity, 12 months or longer, Fair Value	22,115	75,603
Securities held to maturity, 12 months or longer, Unrealized Losses	235	2,597
Securities held to maturity, Fair Value, Total	33,746	75,603
Securities held to maturity, Unrealized Losses, Total	261	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	3,575
Securities held to maturity, Less than 12 months, Unrealized Losses	52
Securities held to maturity, 12 months or longer, Fair Value	3,875	17,263
Securities held to maturity, 12 months or longer, Unrealized Losses	46	535
Securities held to maturity, Fair Value, Total	7,450	17,263
Securities held to maturity, Unrealized Losses, Total	98	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	74,468	251
Securities available for sale, Less than 12 months, Unrealized Losses	605	1
Securities available for sale, 12 months or longer, Fair Value	31,046	286,262
Securities available for sale, 12 months or longer, Unrealized Losses	313	7,675
Securities available for sale, Fair Value, Total	105,514	286,513
Securities available for sale, Unrealized Losses, Total	918	7,676
Securities held to maturity, Less than 12 months, Fair Value	24,261	14,768
Securities held to maturity, Less than 12 months, Unrealized Losses	114	90
Securities held to maturity, 12 months or longer, Fair Value	58,860	184,973
Securities held to maturity, 12 months or longer, Unrealized Losses	642	6,598
Securities held to maturity, Fair Value, Total	83,121	199,741
Securities held to maturity, Unrealized Losses, Total	756	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	63,435	251
Securities available for sale, Less than 12 months, Unrealized Losses	548	1
Securities available for sale, 12 months or longer, Fair Value	21,217	247,615
Securities available for sale, 12 months or longer, Unrealized Losses	140	6,324
Securities available for sale, Fair Value, Total	84,652	247,866
Securities available for sale, Unrealized Losses, Total	688	6,325
Securities held to maturity, Less than 12 months, Fair Value		1,518
Securities held to maturity, Less than 12 months, Unrealized Losses		3
Securities held to maturity, 12 months or longer, Fair Value	1,078	8,695
Securities held to maturity, 12 months or longer, Unrealized Losses	1	258
Securities held to maturity, Fair Value, Total	1,078	10,213
Securities held to maturity, Unrealized Losses, Total	1	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	889
Securities available for sale, Less than 12 months, Unrealized Losses	6
Securities available for sale, 12 months or longer, Fair Value	9,813	33,918
Securities available for sale, 12 months or longer, Unrealized Losses	173	1,275
Securities available for sale, Fair Value, Total	10,702	33,918
Securities available for sale, Unrealized Losses, Total	179	1,275
Securities held to maturity, Less than 12 months, Fair Value		1,467
Securities held to maturity, Less than 12 months, Unrealized Losses		5
Securities held to maturity, 12 months or longer, Fair Value	2,621	2,923
Securities held to maturity, 12 months or longer, Unrealized Losses	26	188
Securities held to maturity, Fair Value, Total	2,621	4,390
Securities held to maturity, Unrealized Losses, Total	26	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, 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		4,667
Securities available for sale, Unrealized Losses, Total		76
Securities held to maturity, Less than 12 months, Fair Value	848	11,783
Securities held to maturity, Less than 12 months, Unrealized Losses	1	82
Securities held to maturity, 12 months or longer, Fair Value	5,799	22,516
Securities held to maturity, 12 months or longer, Unrealized Losses	39	841
Securities held to maturity, Fair Value, Total	6,647	34,299
Securities held to maturity, Unrealized Losses, Total	$ 40	$ 923

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