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Investment Securities (Investments' Gross Unrealized Losses And Fair Value) (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
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Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | $ 309,087 | $ 335,030
Securities available for sale, Less than 12 months, Unrealized Losses | 6,701 | 14,778
Securities available for sale, 12 months or longer, Fair Value | 83,984 | 50,928
Securities available for sale, 12 months or longer, Unrealized Losses | 4,978 | 2,818
Securities available for sale, Fair Value, Total | 393,071 | 385,958
Securities available for sale, Unrealized Losses, Total | 11,679 | 17,596
Securities held to maturity, Less than 12 months, Fair Value | 319,994 | 407,299
Securities held to maturity, Less than 12 months, Unrealized Losses | 6,764 | 15,246
Securities held to maturity, 12 months or longer, Fair Value | 83,984 | 50,928
Securities held to maturity, 12 months or longer, Unrealized Losses | 4,978 | 2,818
Securities held to maturity, Unrealized Losses, Total | 403,978 | 458,227
Securities held to maturity, Unrealized Losses, Total | 11,742 | 18,064
U.S. Government Agencies And Government Sponsored Enterprises [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 82,112 | 86,177
Securities available for sale, Less than 12 months, Unrealized Losses | 1,072 | 2,788
Securities available for sale, 12 months or longer, Fair Value | 22,184 | 2,717
Securities available for sale, 12 months or longer, Unrealized Losses | 1,060 | 14
Securities available for sale, Fair Value, Total | 104,296 | 88,894
Securities available for sale, Unrealized Losses, Total | 2,132 | 2,802
State And Political Subdivisions [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities held to maturity, Less than 12 months, Fair Value | 10,907 | 72,269
Securities held to maturity, Less than 12 months, Unrealized Losses | 63 | 468
Securities held to maturity, Unrealized Losses, Total | 10,907 | 72,269
Securities held to maturity, Unrealized Losses, Total | 63 | 468
Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 226,975 | 248,853
Securities available for sale, Less than 12 months, Unrealized Losses | 5,629 | 11,990
Securities available for sale, 12 months or longer, Fair Value | 61,800 | 48,211
Securities available for sale, 12 months or longer, Unrealized Losses | 3,918 | 2,804
Securities available for sale, Fair Value, Total | 288,775 | 297,064
Securities available for sale, Unrealized Losses, Total | 9,547 | 14,794
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 96,533 | 103,778
Securities available for sale, Less than 12 months, Unrealized Losses | 2,416 | 3,491
Securities available for sale, 12 months or longer, Fair Value | 25,166 | 20,689
Securities available for sale, 12 months or longer, Unrealized Losses | 1,368 | 1,319
Securities available for sale, Fair Value, Total | 121,699 | 124,467
Securities available for sale, Unrealized Losses, Total | 3,784 | 4,810
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 8,490 | 14,166
Securities available for sale, Less than 12 months, Unrealized Losses | 130 | 205
Securities available for sale, Fair Value, Total | 8,490 | 14,166
Securities available for sale, Unrealized Losses, Total | 130 | 205
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 6,097 | 14,226
Securities available for sale, Less than 12 months, Unrealized Losses | 113 | 142
Securities available for sale, Fair Value, Total | 6,097 | 14,226
Securities available for sale, Unrealized Losses, Total | 113 | 142
Collateralized Mortgage Obligations [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 115,855 | 116,683
Securities available for sale, Less than 12 months, Unrealized Losses | 2,970 | 8,152
Securities available for sale, 12 months or longer, Fair Value | 36,634 | 27,522
Securities available for sale, 12 months or longer, Unrealized Losses | 2,550 | 1,485
Securities available for sale, Fair Value, Total | 152,489 | 144,205
Securities available for sale, Unrealized Losses, Total | 5,520 | 9,637
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 35,545 | 35,632
Securities available for sale, Less than 12 months, Unrealized Losses | 656 | 2,586
Securities available for sale, 12 months or longer, Fair Value | 15,645 | 11,760
Securities available for sale, 12 months or longer, Unrealized Losses | 1,052 | 609
Securities available for sale, Fair Value, Total | 51,190 | 47,392
Securities available for sale, Unrealized Losses, Total | 1,708 | 3,195
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 71,893 | 72,655
Securities available for sale, Less than 12 months, Unrealized Losses | 2,158 | 4,980
Securities available for sale, 12 months or longer, Fair Value | 20,989 | 15,762
Securities available for sale, 12 months or longer, Unrealized Losses | 1,498 | 876
Securities available for sale, Fair Value, Total | 92,882 | 88,417
Securities available for sale, Unrealized Losses, Total | 3,656 | 5,856
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Securities available for sale, Less than 12 months, Fair Value | 8,417 | 8,396
Securities available for sale, Less than 12 months, Unrealized Losses | 156 | 586
Securities available for sale, Fair Value, Total | 8,417 | 8,396
Securities available for sale, Unrealized Losses, Total | $ 156 | $ 586

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