Investment Securities (Investments Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	$ 14,276	$ 251
Securities available for sale, Less than 12 months, Unrealized Losses	29	1
Securities available for sale, 12 months or longer, Fair Value	102,611	438,290
Securities available for sale, 12 months or longer, Unrealized Losses	653	10,749
Securities available for sale, Fair Value, Total	116,887	438,541
Securities available for sale, Unrealized Losses, Total	682	10,750
Securities held to maturity, Less than 12 months, Fair Value	9,185	50,519
Securities held to maturity, Less than 12 months, Unrealized Losses	11	181
Securities held to maturity, 12 months or longer, Fair Value	130,963	234,507
Securities held to maturity, 12 months or longer, Unrealized Losses	1,543	7,718
Securities held to maturity, Fair Value, Total	140,148	285,026
Securities held to maturity, Unrealized Losses, Total	1,554	7,899
Total Securities, Less than 12 months, Fair Value	23,461	50,770
Total Securities, Less than 12 months, Unrealized Losses	40	182
Total Securities, 12 months or longer, Fair Value	233,574	672,797
Total Securities, 12 months or longer, Unrealized Losses	2,196	18,467
Total Securities, Fair Value	257,035	723,567
Total Securities, Unrealized Losses	2,236	18,649
U.S. Government Agency And Government Sponsored Enterprises [Member]
Investment [Line Items]
Securities available for sale, 12 months or longer, Fair Value	18,952	152,028
Securities available for sale, 12 months or longer, Unrealized Losses	58	3,074
Securities available for sale, Fair Value, Total	18,952	152,028
Securities available for sale, Unrealized Losses, Total	58	3,074
State And Political Subdivisions [Member]
Investment [Line Items]
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	4,631	49,534
Securities held to maturity, 12 months or longer, Unrealized Losses	19	1,120
Securities held to maturity, Fair Value, Total	4,631	85,285
Securities held to maturity, Unrealized Losses, Total	19	1,211
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	67
Securities available for sale, Less than 12 months, Unrealized Losses	1
Securities available for sale, 12 months or longer, Fair Value	16	56
Securities available for sale, Fair Value, Total	83	56
Securities available for sale, Unrealized Losses, Total	1
Securities held to maturity, Less than 12 months, Fair Value	6,763
Securities held to maturity, Less than 12 months, Unrealized Losses	8
Securities held to maturity, 12 months or longer, Fair Value	37,056	57,973
Securities held to maturity, 12 months or longer, Unrealized Losses	584	2,179
Securities held to maturity, Fair Value, Total	43,819	57,973
Securities held to maturity, Unrealized Losses, Total	592	2,179
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Securities available for sale, 12 months or longer, Fair Value	5	6
Securities available for sale, Fair Value, Total	5	6
Securities held to maturity, 12 months or longer, Fair Value	52,528	75,603
Securities held to maturity, 12 months or longer, Unrealized Losses	535	2,597
Securities held to maturity, Fair Value, Total	52,528	75,603
Securities held to maturity, Unrealized Losses, Total	535	2,597
Collateralized Mortgage Obligations [Member] \| Government National Mortgage Association [Member]
Investment [Line Items]
Securities held to maturity, 12 months or longer, Fair Value	11,586	17,263
Securities held to maturity, 12 months or longer, Unrealized Losses	93	535
Securities held to maturity, Fair Value, Total	11,586	17,263
Securities held to maturity, Unrealized Losses, Total	93	535
Mortgage-Backed Securities [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	14,276	251
Securities available for sale, Less than 12 months, Unrealized Losses	29	1
Securities available for sale, 12 months or longer, Fair Value	83,659	286,262
Securities available for sale, 12 months or longer, Unrealized Losses	595	7,675
Securities available for sale, Fair Value, Total	97,935	286,513
Securities available for sale, Unrealized Losses, Total	624	7,676
Securities held to maturity, Less than 12 months, Fair Value	9,185	14,768
Securities held to maturity, Less than 12 months, Unrealized Losses	11	90
Securities held to maturity, 12 months or longer, Fair Value	126,332	184,973
Securities held to maturity, 12 months or longer, Unrealized Losses	1,524	6,598
Securities held to maturity, Fair Value, Total	135,517	199,741
Securities held to maturity, Unrealized Losses, Total	1,535	6,688
Mortgage-Backed Securities [Member] \| Federal National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	14,209	251
Securities available for sale, Less than 12 months, Unrealized Losses	28	1
Securities available for sale, 12 months or longer, Fair Value	59,305	247,615
Securities available for sale, 12 months or longer, Unrealized Losses	339	6,324
Securities available for sale, Fair Value, Total	73,514	247,866
Securities available for sale, Unrealized Losses, Total	367	6,325
Securities held to maturity, Less than 12 months, Fair Value	2,422	1,518
Securities held to maturity, Less than 12 months, Unrealized Losses	3	3
Securities held to maturity, 12 months or longer, Fair Value	3,442	8,695
Securities held to maturity, 12 months or longer, Unrealized Losses	30	258
Securities held to maturity, Fair Value, Total	5,864	10,213
Securities held to maturity, Unrealized Losses, Total	33	261
Mortgage-Backed Securities [Member] \| Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Securities available for sale, 12 months or longer, Fair Value	24,333	33,918
Securities available for sale, 12 months or longer, Unrealized Losses	256	1,275
Securities available for sale, Fair Value, Total	24,333	33,918
Securities available for sale, Unrealized Losses, Total	256	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	2,643	2,923
Securities held to maturity, 12 months or longer, Unrealized Losses	65	188
Securities held to maturity, Fair Value, Total	2,643	4,390
Securities held to maturity, Unrealized Losses, Total	65	193
Mortgage-Backed Securities [Member] \| Government National Mortgage Association [Member]
Investment [Line Items]
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		11,783
Securities held to maturity, Less than 12 months, Unrealized Losses		82
Securities held to maturity, 12 months or longer, Fair Value	19,077	22,516
Securities held to maturity, 12 months or longer, Unrealized Losses	217	841
Securities held to maturity, Fair Value, Total	19,077	34,299
Securities held to maturity, Unrealized Losses, Total	$ 217	$ 923

Amount of accumulated pre-tax unrealized loss on securities.

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Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months.

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