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Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2016 | Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 130,278 | $ 201,054
Net Unrealized Gains (Losses) | 194 | 300
Carrying Value | 130,472 | 201,354
Unrecognized Holding Gains | 5,622 | 8,190
Unrecognized Holding Losses | 0 | 0
Held-to-maturity Securities, Fair Value | $ 136,094 | 209,544
Held-to-maturity Securities Average Duration | 1 year 7 months |
Obligations of States and Political Subdivisions [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 104,159 | 175,269
Net Unrealized Gains (Losses) | 414 | 848
Carrying Value | 104,573 | 176,117
Unrecognized Holding Gains | 3,256 | 5,763
Unrecognized Holding Losses | 0 | 0
Held-to-maturity Securities, Fair Value | 107,829 | 181,880
Corporate Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 23,722 | 20,228
Net Unrealized Gains (Losses) | (165) | (185)
Carrying Value | 23,557 | 20,043
Unrecognized Holding Gains | 2,294 | 1,972
Unrecognized Holding Losses | 0 | 0
Held-to-maturity Securities, Fair Value | 25,851 | 22,015
Asset-Backed Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 51 | 1,030
Net Unrealized Gains (Losses) | 0 | (120)
Carrying Value | 51 | 910
Unrecognized Holding Gains | 0 | 118
Unrecognized Holding Losses | 0 | 0
Held-to-maturity Securities, Fair Value | 51 | 1,028
Commercial Mortgage Backed Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 2,346 | 4,527
Net Unrealized Gains (Losses) | (55) | (243)
Carrying Value | 2,291 | 4,284
Unrecognized Holding Gains | 72 | 337
Unrecognized Holding Losses | 0 | 0
Held-to-maturity Securities, Fair Value | $ 2,363 | $ 4,621

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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 (a) -URI http://asc.fasb.org/extlink&oid=73527792&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=65884222&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 (f) -URI http://asc.fasb.org/extlink&oid=73527792&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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