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Investment Securities (Investments Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 70 | $ 251
Securities available for sale, Less than 12 months, Unrealized Losses | 1 | 1
Securities available for sale, 12 months or longer, Fair Value | 373,183 | 438,290
Securities available for sale, 12 months or longer, Unrealized Losses | 3,814 | 10,749
Securities available for sale, Fair Value, Total | 373,253 | 438,541
Securities available for sale, Unrealized Losses, Total | 3,815 | 10,750
Securities held to maturity, Less than 12 months, Fair Value | 9,235 | 50,519
Securities held to maturity, Less than 12 months, Unrealized Losses | 17 | 181
Securities held to maturity, 12 months or longer, Fair Value | 201,487 | 234,507
Securities held to maturity, 12 months or longer, Unrealized Losses | 4,412 | 7,718
Securities held to maturity, Fair Value, Total | 210,722 | 285,026
Securities held to maturity, Unrealized Losses, Total | 4,429 | 7,899
Total Securities, Less than 12 months, Fair Value | 9,305 | 50,770
Total Securities, Less than 12 months, Unrealized Losses | 18 | 182
Total Securities, 12 months or longer, Fair Value | 574,670 | 672,797
Total Securities, 12 months or longer, Unrealized Losses | 8,226 | 18,467
Total Securities, Fair Value | 583,975 | 723,567
Total Securities, Unrealized Losses | 8,244 | 18,649
U.S. Government Agency And Government Sponsored Enterprises [Member] |  |
Investment [Line Items] |  |
Securities available for sale, 12 months or longer, Fair Value | 112,425 | 152,028
Securities available for sale, 12 months or longer, Unrealized Losses | 809 | 3,074
Securities available for sale, Fair Value, Total | 112,425 | 152,028
Securities available for sale, Unrealized Losses, Total | 809 | 3,074
State And Political Subdivisions [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 2,717 | 35,751
Securities held to maturity, Less than 12 months, Unrealized Losses | 1 | 91
Securities held to maturity, 12 months or longer, Fair Value | 24,312 | 49,534
Securities held to maturity, 12 months or longer, Unrealized Losses | 224 | 1,120
Securities held to maturity, Fair Value, Total | 27,029 | 85,285
Securities held to maturity, Unrealized Losses, Total | 225 | 1,211
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 70 |
Securities available for sale, Less than 12 months, Unrealized Losses | 1 |
Securities available for sale, 12 months or longer, Fair Value | 19 | 56
Securities available for sale, Fair Value, Total | 89 | 56
Securities available for sale, Unrealized Losses, Total | 1 |
Securities held to maturity, 12 months or longer, Fair Value | 56,114 | 57,973
Securities held to maturity, 12 months or longer, Unrealized Losses | 1,474 | 2,179
Securities held to maturity, Fair Value, Total | 56,114 | 57,973
Securities held to maturity, Unrealized Losses, Total | 1,474 | 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 | 6 | 6
Securities available for sale, Fair Value, Total | 6 | 6
Securities held to maturity, 12 months or longer, Fair Value | 72,277 | 75,603
Securities held to maturity, 12 months or longer, Unrealized Losses | 1,624 | 2,597
Securities held to maturity, Fair Value, Total | 72,277 | 75,603
Securities held to maturity, Unrealized Losses, Total | 1,624 | 2,597
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, 12 months or longer, Fair Value | 16,561 | 17,263
Securities held to maturity, 12 months or longer, Unrealized Losses | 363 | 535
Securities held to maturity, Fair Value, Total | 16,561 | 17,263
Securities held to maturity, Unrealized Losses, Total | 363 | 535
Mortgage-Backed Securities [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 70 | 251
Securities available for sale, Less than 12 months, Unrealized Losses | 1 | 1
Securities available for sale, 12 months or longer, Fair Value | 260,758 | 286,262
Securities available for sale, 12 months or longer, Unrealized Losses | 3,005 | 7,675
Securities available for sale, Fair Value, Total | 260,828 | 286,513
Securities available for sale, Unrealized Losses, Total | 3,006 | 7,676
Securities held to maturity, Less than 12 months, Fair Value | 6,518 | 14,768
Securities held to maturity, Less than 12 months, Unrealized Losses | 16 | 90
Securities held to maturity, 12 months or longer, Fair Value | 177,175 | 184,973
Securities held to maturity, 12 months or longer, Unrealized Losses | 4,188 | 6,598
Securities held to maturity, Fair Value, Total | 183,693 | 199,741
Securities held to maturity, Unrealized Losses, Total | 4,204 | 6,688
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 251
Securities available for sale, Less than 12 months, Unrealized Losses |  | 1
Securities available for sale, 12 months or longer, Fair Value | 224,846 | 247,615
Securities available for sale, 12 months or longer, Unrealized Losses | 2,366 | 6,324
Securities available for sale, Fair Value, Total | 224,846 | 247,866
Securities available for sale, Unrealized Losses, Total | 2,366 | 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 | 7,696 | 8,695
Securities held to maturity, 12 months or longer, Unrealized Losses | 114 | 258
Securities held to maturity, Fair Value, Total | 7,696 | 10,213
Securities held to maturity, Unrealized Losses, Total | 114 | 261
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, 12 months or longer, Fair Value | 31,365 | 33,918
Securities available for sale, 12 months or longer, Unrealized Losses | 634 | 1,275
Securities available for sale, Fair Value, Total | 31,365 | 33,918
Securities available for sale, Unrealized Losses, Total | 634 | 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 | 2,619 | 2,923
Securities held to maturity, 12 months or longer, Unrealized Losses | 109 | 188
Securities held to maturity, Fair Value, Total | 2,619 | 4,390
Securities held to maturity, Unrealized Losses, Total | 109 | 193
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, 12 months or longer, Fair Value | 4,522 | 4,667
Securities available for sale, 12 months or longer, Unrealized Losses | 5 | 76
Securities available for sale, Fair Value, Total | 4,522 | 4,667
Securities available for sale, Unrealized Losses, Total | 5 | 76
Securities held to maturity, Less than 12 months, Fair Value | 6,518 | 11,783
Securities held to maturity, Less than 12 months, Unrealized Losses | 16 | 82
Securities held to maturity, 12 months or longer, Fair Value | 21,908 | 22,516
Securities held to maturity, 12 months or longer, Unrealized Losses | 504 | 841
Securities held to maturity, Fair Value, Total | 28,426 | 34,299
Securities held to maturity, Unrealized Losses, Total | $ 520 | $ 923

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