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Securities Available-for-Sale - Unrealized Gains (Losses) (Details) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
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Investments, Debt and Equity Securities [Abstract] |  |
Total unrealized gains/(losses) on securities available for sale, Gross Unrealized Gains | $ 9,925 | $ 10,754
Total unrealized gains/(losses) on securities available for sale, Gross Unrealized Losses | (2,443) | (3,472)
Total unrealized gains/(losses) on securities available for sale, Net Unrealized Gains/(Losses) | 7,482 | 7,282
Income tax expense/(benefit), Gross Unrealized Gains | (3,485) | (3,776)
Income tax expense/(benefit), Gross Unrealized Losses | 858 | 1,219
Income tax expense/(benefit), Net Unrealized Gains/(Losses) | (2,627) | (2,557)
Net unrealized gains/(losses), net of tax included in accumulated other comprehensive income/(loss), Gross Unrealized Gains | 6,440 | 6,978
Net unrealized gains/(losses), net of tax included in accumulated other comprehensive income/(loss), Gross Unrealized Losses | (1,585) | (2,253)
Net unrealized gains/(losses), net of tax included in accumulated other comprehensive income/(loss), Net Unrealized Gains/(Losses) | $ 4,855 | $ 4,725

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- Definition Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580 + Details
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