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Investment Securities (Investments' Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 13,821 | $ 232,913
Securities available for sale, Less than 12 months, Unrealized Losses | 16 | 3,312
Securities available for sale, 12 months or longer, Fair Value | 27,521 | 35,864
Securities available for sale, 12 months or longer, Unrealized Losses | 84 | 513
Securities available for sale, Fair Value, Total | 41,342 | 268,777
Securities available for sale, Unrealized Losses, Total | 100 | 3,825
Securities held to maturity, Less than 12 months, Fair Value | 23,425 | 167,386
Securities held to maturity, Less than 12 months, Unrealized Losses | 42 | 2,281
Securities held to maturity, 12 months or longer, Fair Value | 3,773 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 29 |
Securities held to maturity, Fair Value, Total | 27,198 | 167,386
Securities held to maturity, Unrealized Losses, Total | 71 | 2,281
Total Securities, Less than 12 months, Fair Value | 37,246 | 400,299
Total Securities, Less than 12 months, Unrealized Losses | 58 | 5,593
Total Securities, 12 months or longer, Fair Value | 31,294 | 35,864
Total Securities, 12 months or longer, Unrealized Losses | 113 | 513
Total Securities, Fair Value | 68,540 | 436,163
Total Securities, Unrealized Losses | 171 | 6,106
U.S. Government Agencies And Government Sponsored Enterprises [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 391 | 82,298
Securities available for sale, Less than 12 months, Unrealized Losses | 1 | 735
Securities available for sale, 12 months or longer, Fair Value | 7,482 | 26,302
Securities available for sale, 12 months or longer, Unrealized Losses | 6 | 314
Securities available for sale, Fair Value, Total | 7,873 | 108,600
Securities available for sale, Unrealized Losses, Total | 7 | 1,049
State And Political Subdivisions [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 2,477 | 3,075
Securities held to maturity, Less than 12 months, Unrealized Losses | 1 | 4
Securities held to maturity, Fair Value, Total | 2,477 | 3,075
Securities held to maturity, Unrealized Losses, Total | 1 | 4
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 7,778
Securities available for sale, Less than 12 months, Unrealized Losses |  | 154
Securities available for sale, Fair Value, Total |  | 7,778
Securities available for sale, Unrealized Losses, Total |  | 154
Securities held to maturity, Less than 12 months, Fair Value | 6,895 | 55,973
Securities held to maturity, Less than 12 months, Unrealized Losses | 15 | 818
Securities held to maturity, Fair Value, Total | 6,895 | 55,973
Securities held to maturity, Unrealized Losses, Total | 15 | 818
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 4,998
Securities available for sale, Less than 12 months, Unrealized Losses |  | 91
Securities available for sale, Fair Value, Total |  | 4,998
Securities available for sale, Unrealized Losses, Total |  | 91
Securities held to maturity, Less than 12 months, Fair Value | 5,100 | 79,323
Securities held to maturity, Less than 12 months, Unrealized Losses | 5 | 1,120
Securities held to maturity, Fair Value, Total | 5,100 | 79,323
Securities held to maturity, Unrealized Losses, Total | 5 | 1,120
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 3,366 | 14,559
Securities held to maturity, Less than 12 months, Unrealized Losses | 7 | 101
Securities held to maturity, Fair Value, Total | 3,366 | 14,559
Securities held to maturity, Unrealized Losses, Total | 7 | 101
Mortgage-Backed Securities [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 13,430 | 150,615
Securities available for sale, Less than 12 months, Unrealized Losses | 15 | 2,577
Securities available for sale, 12 months or longer, Fair Value | 20,039 | 9,562
Securities available for sale, 12 months or longer, Unrealized Losses | 78 | 199
Securities available for sale, Fair Value, Total | 33,469 | 160,177
Securities available for sale, Unrealized Losses, Total | 93 | 2,776
Securities held to maturity, Less than 12 months, Fair Value | 20,948 | 164,311
Securities held to maturity, Less than 12 months, Unrealized Losses | 41 | 2,277
Securities held to maturity, 12 months or longer, Fair Value | 3,773 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 29 |
Securities held to maturity, Fair Value, Total | 24,721 | 164,311
Securities held to maturity, Unrealized Losses, Total | 70 | 2,277
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 12,098 | 123,774
Securities available for sale, Less than 12 months, Unrealized Losses | 3 | 2,134
Securities available for sale, 12 months or longer, Fair Value | 15,781 | 9,562
Securities available for sale, 12 months or longer, Unrealized Losses | 50 | 199
Securities available for sale, Fair Value, Total | 27,879 | 133,336
Securities available for sale, Unrealized Losses, Total | 53 | 2,333
Securities held to maturity, Less than 12 months, Fair Value | 1,362 | 5,666
Securities held to maturity, Less than 12 months, Unrealized Losses | 2 | 79
Securities held to maturity, Fair Value, Total | 1,362 | 5,666
Securities held to maturity, Unrealized Losses, Total | 2 | 79
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 12,660
Securities available for sale, Less than 12 months, Unrealized Losses |  | 194
Securities available for sale, 12 months or longer, Fair Value | 4,258 |
Securities available for sale, 12 months or longer, Unrealized Losses | 28 |
Securities available for sale, Fair Value, Total | 4,258 | 12,660
Securities available for sale, Unrealized Losses, Total | 28 | 194
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 1,332 | 1,405
Securities available for sale, Less than 12 months, Unrealized Losses | 12 | 4
Securities available for sale, Fair Value, Total | 1,332 | 1,405
Securities available for sale, Unrealized Losses, Total | 12 | 4
Securities held to maturity, Less than 12 months, Fair Value | 4,225 | 8,790
Securities held to maturity, Less than 12 months, Unrealized Losses | 12 | 159
Securities held to maturity, 12 months or longer, Fair Value | 3,773 |
Securities held to maturity, 12 months or longer, Unrealized Losses | 29 |
Securities held to maturity, Fair Value, Total | 7,998 | 8,790
Securities held to maturity, Unrealized Losses, Total | $ 41 | $ 159

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