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Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Amortized Cost | $ 42,150 | $ 101,397
Net Unrealized Gains (Losses) | (21) | 159
Total HTM fixed income securities carrying value | 42,129 | 101,556
Unrecognized Holding Gains | 2,026 | 3,813
Unrecognized Holding Losses | (55) | (158)
Total HTM fixed income securities fair value | 44,100 | 105,211
Obligations of States and Political Subdivisions [Member] |  |
Amortized Cost | 25,154 | 77,466
Net Unrealized Gains (Losses) | 84 | 317
Total HTM fixed income securities carrying value | 25,238 | 77,783
Unrecognized Holding Gains | 1,023 | 2,133
Unrecognized Holding Losses | 0 | 0
Total HTM fixed income securities fair value | 26,261 | 79,916
Corporate Securities [Member] |  |
Amortized Cost | 16,996 | 22,711
Net Unrealized Gains (Losses) | (105) | (143)
Total HTM fixed income securities carrying value | 16,891 | 22,568
Unrecognized Holding Gains | 1,003 | 1,665
Unrecognized Holding Losses | (55) | (158)
Total HTM fixed income securities fair value | $ 17,839 | 24,075
Commercial Mortgage Backed Securities [Member] |  |
Amortized Cost |  | 1,220
Net Unrealized Gains (Losses) |  | (15)
Total HTM fixed income securities carrying value |  | 1,205
Unrecognized Holding Gains |  | 15
Unrecognized Holding Losses |  | 0
Total HTM fixed income securities fair value |  | $ 1,220

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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=82897076&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=75030427&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=82897076&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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