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Investment Securities (Investments' Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands | Sep. 30, 2016 | Dec. 31, 2015
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Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 6,562 | $ 232,913
Securities available for sale, Less than 12 months, Unrealized Losses | 28 | 3,312
Securities available for sale, 12 months or longer, Fair Value | 1,515 | 35,864
Securities available for sale, 12 months or longer, Unrealized Losses | 5 | 513
Securities available for sale, Fair Value, Total | 8,077 | 268,777
Securities available for sale, Unrealized Losses, Total | 33 | 3,825
Securities held to maturity, Less than 12 months, Fair Value | 76,519 | 167,386
Securities held to maturity, Less than 12 months, Unrealized Losses | 277 | 2,281
Securities held to maturity, 12 months or longer, Fair Value | 5,606 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 19 |
Securities held to maturity, Fair Value, Total | 82,125 | 167,386
Securities held to maturity, Unrealized Losses, Total | 296 | 2,281
Total Securities, Less than 12 months, Fair Value | 83,081 | 400,299
Total Securities, Less than 12 months, Unrealized Losses | 305 | 5,593
Total Securities, 12 months or longer, Fair Value | 7,121 | 35,864
Total Securities, 12 months or longer, Unrealized Losses | 24 | 513
Total Securities, Fair Value | 90,202 | 436,163
Total Securities, Unrealized Losses | 329 | 6,106
U.S. Government Agencies And Government Sponsored Enterprises [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 82,298
Securities available for sale, Less than 12 months, Unrealized Losses |  | 735
Securities available for sale, 12 months or longer, Fair Value | 1,515 | 26,302
Securities available for sale, 12 months or longer, Unrealized Losses | 5 | 314
Securities available for sale, Fair Value, Total | 1,515 | 108,600
Securities available for sale, Unrealized Losses, Total | 5 | 1,049
State And Political Subdivisions [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 12,710 | 3,075
Securities held to maturity, Less than 12 months, Unrealized Losses | 45 | 4
Securities held to maturity, Fair Value, Total | 12,710 | 3,075
Securities held to maturity, Unrealized Losses, Total | 45 | 4
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 326 | 7,778
Securities available for sale, Less than 12 months, Unrealized Losses | 1 | 154
Securities available for sale, Fair Value, Total | 326 | 7,778
Securities available for sale, Unrealized Losses, Total | 1 | 154
Securities held to maturity, Less than 12 months, Fair Value | 26,315 | 55,973
Securities held to maturity, Less than 12 months, Unrealized Losses | 89 | 818
Securities held to maturity, 12 months or longer, Fair Value | 3,600 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 16 |
Securities held to maturity, Fair Value, Total | 29,915 | 55,973
Securities held to maturity, Unrealized Losses, Total | 105 | 818
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 73 | 4,998
Securities available for sale, Less than 12 months, Unrealized Losses | 1 | 91
Securities available for sale, Fair Value, Total | 73 | 4,998
Securities available for sale, Unrealized Losses, Total | 1 | 91
Securities held to maturity, Less than 12 months, Fair Value | 27,838 | 79,323
Securities held to maturity, Less than 12 months, Unrealized Losses | 127 | 1,120
Securities held to maturity, 12 months or longer, Fair Value | 496 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 1 |
Securities held to maturity, Fair Value, Total | 28,334 | 79,323
Securities held to maturity, Unrealized Losses, Total | 128 | 1,120
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 6,677 | 14,559
Securities held to maturity, Less than 12 months, Unrealized Losses | 14 | 101
Securities held to maturity, 12 months or longer, Fair Value | 1,510 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 2 |
Securities held to maturity, Fair Value, Total | 8,187 | 14,559
Securities held to maturity, Unrealized Losses, Total | 16 | 101
Mortgage-Backed Securities [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 6,562 | 150,615
Securities available for sale, Less than 12 months, Unrealized Losses | 28 | 2,577
Securities available for sale, 12 months or longer, Fair Value |  | 9,562
Securities available for sale, 12 months or longer, Unrealized Losses |  | 199
Securities available for sale, Fair Value, Total | 6,562 | 160,177
Securities available for sale, Unrealized Losses, Total | 28 | 2,776
Securities held to maturity, Less than 12 months, Fair Value | 63,809 | 164,311
Securities held to maturity, Less than 12 months, Unrealized Losses | 232 | 2,277
Securities held to maturity, 12 months or longer, Fair Value | 5,606 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 19 |
Securities held to maturity, Fair Value, Total | 69,415 | 164,311
Securities held to maturity, Unrealized Losses, Total | 251 | 2,277
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 123,774
Securities available for sale, Less than 12 months, Unrealized Losses |  | 2,134
Securities available for sale, 12 months or longer, Fair Value |  | 9,562
Securities available for sale, 12 months or longer, Unrealized Losses |  | 199
Securities available for sale, Fair Value, Total |  | 133,336
Securities available for sale, Unrealized Losses, Total |  | 2,333
Securities held to maturity, Less than 12 months, Fair Value |  | 5,666
Securities held to maturity, Less than 12 months, Unrealized Losses |  | 79
Securities held to maturity, Fair Value, Total |  | 5,666
Securities held to maturity, Unrealized Losses, Total |  | 79
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 4,992 | 12,660
Securities available for sale, Less than 12 months, Unrealized Losses | 11 | 194
Securities available for sale, Fair Value, Total | 4,992 | 12,660
Securities available for sale, Unrealized Losses, Total | 11 | 194
Securities held to maturity, Less than 12 months, Fair Value | 1,349 |
Securities held to maturity, Less than 12 months, Unrealized Losses | 1 |
Securities held to maturity, Fair Value, Total | 1,349 |
Securities held to maturity, Unrealized Losses, Total | 1 |
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 1,171 | 1,405
Securities available for sale, Less than 12 months, Unrealized Losses | 15 | 4
Securities available for sale, Fair Value, Total | 1,171 | 1,405
Securities available for sale, Unrealized Losses, Total | 15 | 4
Securities held to maturity, Less than 12 months, Fair Value | 1,630 | 8,790
Securities held to maturity, Less than 12 months, Unrealized Losses | 1 | 159
Securities held to maturity, Fair Value, Total | 1,630 | 8,790
Securities held to maturity, Unrealized Losses, Total | $ 1 | $ 159

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