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Investments (Held-To-Maturity Securities Disclosure) (Details) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 64,977 | $ 101,397
Net Unrealized Gains (Losses) | 12 | 159
HTM, Carrying Value | 64,989 | 101,556
Unrecognized Holding Gains | 2,727 | 3,813
Unrecognized Holding Losses | 0 | (158)
Held-to-maturity Securities, Fair Value | 67,716 | 105,211
Obligations of States and Political Subdivisions [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 46,551 | 77,466
Net Unrealized Gains (Losses) | 130 | 317
HTM, Carrying Value | 46,681 | 77,783
Unrecognized Holding Gains | 1,442 | 2,133
Unrecognized Holding Losses | 0 | 0
Held-to-maturity Securities, Fair Value | 48,123 | 79,916
Corporate Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 18,426 | 22,711
Net Unrealized Gains (Losses) | (118) | (143)
HTM, Carrying Value | 18,308 | 22,568
Unrecognized Holding Gains | 1,285 | 1,665
Unrecognized Holding Losses | 0 | (158)
Held-to-maturity Securities, Fair Value | $ 19,593 | 24,075
Commercial Mortgage Backed Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost |  | 1,220
Net Unrealized Gains (Losses) |  | (15)
HTM, Carrying Value |  | 1,205
Unrecognized Holding Gains |  | 15
Unrecognized Holding Losses |  | 0
Held-to-maturity 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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- 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=82897076&loc=d3e27232-111563 + Details
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- Definition Amount of accumulated unrealized loss 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 (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 + 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=82897076&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=82897076&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=82897076&loc=d3e27232-111563 + Details
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