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Investment Securities (Summary Of Amortized Cost And Fair Value Of Investment Securities) (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | $ 677,079 | $ 618,166
Securities available for sale, Unrealized Gains | 9,250 | 8,830
Securities available for sale, Unrealized Losses | 11,679 | 17,596
Securities available for sale, Fair Value | 674,650 | 609,400
Securities held to maturity, Amortized Cost | 253,576 | 249,785
Securities held to maturity, Unrealized Losses | 11,742 | 18,064
Securities held to maturity, Fair Value | 256,091 | 250,657
U.S. Government Agencies And Government Sponsored Enterprises [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 190,967 | 135,840
Securities available for sale, Unrealized Gains | 1,659 | 1,414
Securities available for sale, Unrealized Losses | 2,132 | 2,802
Securities available for sale, Fair Value | 190,494 | 134,452
State And Political Subdivisions [Member] |  |
Investment [Line Items] |  |
Securities held to maturity, Amortized Cost | 253,576 | 249,785
Securities held to maturity, Unrealized Gains | 2,578 | 1,340
Securities held to maturity, Unrealized Losses | 63 | 468
Securities held to maturity, Fair Value | 256,091 | 250,657
Mortgage-Backed Securities [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 486,094 | 482,308
Securities available for sale, Unrealized Gains | 7,263 | 7,035
Securities available for sale, Unrealized Losses | 9,547 | 14,794
Securities available for sale, Fair Value | 483,810 | 474,549
Mortgage-Backed Securities [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 174,591 | 173,507
Securities available for sale, Unrealized Gains | 1,561 | 1,511
Securities available for sale, Unrealized Losses | 3,784 | 4,810
Securities available for sale, Fair Value | 172,368 | 170,208
Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 34,713 | 36,737
Securities available for sale, Unrealized Gains | 641 | 562
Securities available for sale, Unrealized Losses | 130 | 205
Securities available for sale, Fair Value | 35,224 | 37,094
Mortgage-Backed Securities [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 60,857 | 61,832
Securities available for sale, Unrealized Gains | 2,164 | 2,152
Securities available for sale, Unrealized Losses | 113 | 142
Securities available for sale, Fair Value | 62,908 | 63,842
Collateralized Mortgage Obligations [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 215,933 | 210,232
Securities available for sale, Unrealized Gains | 2,897 | 2,810
Securities available for sale, Unrealized Losses | 5,520 | 9,637
Securities available for sale, Fair Value | 213,310 | 203,405
Collateralized Mortgage Obligations [Member] | Federal National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 65,427 | 63,838
Securities available for sale, Unrealized Gains | 339 | 261
Securities available for sale, Unrealized Losses | 1,708 | 3,195
Securities available for sale, Fair Value | 64,058 | 60,904
Collateralized Mortgage Obligations [Member] | Federal Home Loan Mortgage Corporation [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 104,334 | 102,660
Securities available for sale, Unrealized Gains | 232 | 169
Securities available for sale, Unrealized Losses | 3,656 | 5,856
Securities available for sale, Fair Value | 100,910 | 96,973
Collateralized Mortgage Obligations [Member] | Government National Mortgage Association [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 46,172 | 43,734
Securities available for sale, Unrealized Gains | 924 | 913
Securities available for sale, Unrealized Losses | 156 | 586
Securities available for sale, Fair Value | 46,940 | 44,061
Collateralized Mortgage Obligations [Member] | Privately Issued [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Unrealized Gains | 1,402 | 1,467
Securities available for sale, Fair Value | 1,402 | 1,467
Asset-Backed Securities [Member] |  |
Investment [Line Items] |  |
Securities available for sale, Amortized Cost | 18 | 18
Securities available for sale, Unrealized Gains | 328 | 381
Securities available for sale, Fair Value | $ 346 | $ 399

X
- Definition Amount of accumulated pre-tax unrealized gains before deducting pre-tax unrealized losses on investments in available-for-sale securities impacting investments. + References No definition available. + Details
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- Definition Amount of accumulated pre-tax unrealized loss before deducting pre-tax unrealized gain on investments in available-for-sale securities impacting investments. + References No definition available. + Details
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- Definition This item represents the excess of amortized cost basis over fair value of securities in a gain position and which are categorized as held-to-maturity. + References No definition available. + Details
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- Definition This item represents the excess of amortized cost basis over fair value of securities in a loss position and which are categorized as held-to-maturity. + References No definition available. + Details
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.6) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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