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Investment Securities (Investments' Gross Unrealized Losses And Fair Value) (Details) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 82,471 | $ 335,030
Securities available for sale, Less than 12 months, Unrealized Losses | 207 | 14,778
Securities available for sale, 12 months or longer, Fair Value | 236,297 | 50,928
Securities available for sale, 12 months or longer, Unrealized Losses | 7,913 | 2,818
Securities available for sale, Fair Value, Total | 318,768 | 385,958
Securities available for sale, Unrealized Losses, Total | 8,120 | 17,596
Securities held to maturity, Less than 12 months, Fair Value | 95,756 | 407,299
Securities held to maturity, Less than 12 months, Unrealized Losses | 285 | 15,246
Securities held to maturity, 12 months or longer, Fair Value | 236,297 | 50,928
Securities held to maturity, 12 months or longer, Unrealized Losses | 7,913 | 2,818
Securities held to maturity, Fair Value, Total | 332,053 | 458,227
Securities held to maturity, Unrealized Losses, Total | 8,198 | 18,064
U.S. Government Agencies And Government Sponsored Enterprises [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 30,830 | 86,177
Securities available for sale, Less than 12 months, Unrealized Losses | 2 | 2,788
Securities available for sale, 12 months or longer, Fair Value | 41,159 | 2,717
Securities available for sale, 12 months or longer, Unrealized Losses | 1,048 | 14
Securities available for sale, Fair Value, Total | 71,989 | 88,894
Securities available for sale, Unrealized Losses, Total | 1,050 | 2,802
State And Political Subdivisions [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 13,285 | 72,269
Securities held to maturity, Less than 12 months, Unrealized Losses | 78 | 468
Securities held to maturity, Fair Value, Total | 13,285 | 72,269
Securities held to maturity, Unrealized Losses, Total | 78 | 468
Mortgage-Backed Securities [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 51,641 | 248,853
Securities available for sale, Less than 12 months, Unrealized Losses | 205 | 11,990
Securities available for sale, 12 months or longer, Fair Value | 195,138 | 48,211
Securities available for sale, 12 months or longer, Unrealized Losses | 6,865 | 2,804
Securities available for sale, Fair Value, Total | 246,779 | 297,064
Securities available for sale, Unrealized Losses, Total | 7,070 | 14,794
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 34,572 | 103,778
Securities available for sale, Less than 12 months, Unrealized Losses | 107 | 3,491
Securities available for sale, 12 months or longer, Fair Value | 64,582 | 20,689
Securities available for sale, 12 months or longer, Unrealized Losses | 2,110 | 1,319
Securities available for sale, Fair Value, Total | 99,154 | 124,467
Securities available for sale, Unrealized Losses, Total | 2,217 | 4,810
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 14,166
Securities available for sale, Less than 12 months, Unrealized Losses |  | 205
Securities available for sale, 12 months or longer, Fair Value | 3,750 |
Securities available for sale, 12 months or longer, Unrealized Losses | 10 |
Securities available for sale, Fair Value, Total | 3,750 | 14,166
Securities available for sale, Unrealized Losses, Total | 10 | 205
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 5,440 | 14,226
Securities available for sale, Less than 12 months, Unrealized Losses | 54 | 142
Securities available for sale, Fair Value, Total | 5,440 | 14,226
Securities available for sale, Unrealized Losses, Total | 54 | 142
Collateralized Mortgage Obligations [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 11,629 | 116,683
Securities available for sale, Less than 12 months, Unrealized Losses | 44 | 8,152
Securities available for sale, 12 months or longer, Fair Value | 126,806 | 27,522
Securities available for sale, 12 months or longer, Unrealized Losses | 4,745 | 1,485
Securities available for sale, Fair Value, Total | 138,435 | 144,205
Securities available for sale, Unrealized Losses, Total | 4,789 | 9,637
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 9,010 | 35,632
Securities available for sale, Less than 12 months, Unrealized Losses | 22 | 2,586
Securities available for sale, 12 months or longer, Fair Value | 37,314 | 11,760
Securities available for sale, 12 months or longer, Unrealized Losses | 1,405 | 609
Securities available for sale, Fair Value, Total | 46,324 | 47,392
Securities available for sale, Unrealized Losses, Total | 1,427 | 3,195
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 2,619 | 72,655
Securities available for sale, Less than 12 months, Unrealized Losses | 22 | 4,980
Securities available for sale, 12 months or longer, Fair Value | 83,809 | 15,762
Securities available for sale, 12 months or longer, Unrealized Losses | 3,267 | 876
Securities available for sale, Fair Value, Total | 86,428 | 88,417
Securities available for sale, Unrealized Losses, Total | 3,289 | 5,856
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value |  | 8,396
Securities available for sale, Less than 12 months, Unrealized Losses |  | 586
Securities available for sale, 12 months or longer, Fair Value | 5,683 |
Securities available for sale, 12 months or longer, Unrealized Losses | 73 |
Securities available for sale, Fair Value, Total | 5,683 | 8,396
Securities available for sale, Unrealized Losses, Total | $ 73 | $ 586

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