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Investments (Held-To-Maturity Securities Disclosure) (Details) (USD $) In Thousands, unless otherwise specified | 9 Months Ended |
--- | --- | ---
Sep. 30, 2014 | Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 334,875 | $ 390,622
Net Unrealized Gains (Losses) | 1,207 | 2,257
Carrying Value | 336,082 | 392,879
Unrecognized Holding Gains | 18,109 | 24,102
Unrecognized Holding Losses | (1) | 0
HTM, Fair Value | 354,190 | 416,981
Held To Maturity securities average duration | 2 years 0 months 0 days |
Foreign Government [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 5,292 | 5,292
Net Unrealized Gains (Losses) | 68 | 131
Carrying Value | 5,360 | 5,423
Unrecognized Holding Gains | 47 | 168
Unrecognized Holding Losses | 0 | 0
HTM, Fair Value | 5,407 | 5,591
Obligations of States and Political Subdivisions [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 301,216 | 348,109
Net Unrealized Gains (Losses) | 2,472 | 4,013
Carrying Value | 303,688 | 352,122
Unrecognized Holding Gains | 13,921 | 17,634
Unrecognized Holding Losses | 0 | 0
HTM, Fair Value | 317,609 | 369,756
Corporate Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 20,303 | 28,174
Net Unrealized Gains (Losses) | (325) | (346)
Carrying Value | 19,978 | 27,828
Unrecognized Holding Gains | 2,749 | 2,446
Unrecognized Holding Losses | (1) | 0
HTM, Fair Value | 22,726 | 30,274
Asset-Backed Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 3,111 | 3,413
Net Unrealized Gains (Losses) | (530) | (655)
Carrying Value | 2,581 | 2,758
Unrecognized Holding Gains | 543 | 657
Unrecognized Holding Losses | 0 | 0
HTM, Fair Value | 3,124 | 3,415
Commercial Mortgage Backed Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 4,953 | 5,634
Net Unrealized Gains (Losses) | (478) | (886)
Carrying Value | 4,475 | 4,748
Unrecognized Holding Gains | 849 | 3,197
Unrecognized Holding Losses | 0 | 0
HTM, Fair Value | $ 5,324 | $ 7,945

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- Definition The remaining aggregate increase (decrease) in the market value of held-to-maturity securities either (i) prior to the securities' transfer to a held-to-maturity designation or (ii) resulting from a non-credit other-than-temporary impairment. + References No definition available. + 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 Amount of accumulated unrealized gain on 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 (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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