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Long-Term Borrowings and Subordinated Debt - Scheduled Annual Maturities and Average Interest Rates (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
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Debt Disclosure [Abstract] |  |  |
2018 Balance | $ 2,496 |  |
2019 Balance | 37,514 |  |
2020 Balance | 2,004 |  |
2021 Balance | 1,057 |  |
2022 Balance | 529 |  |
Thereafter Balance | 3,701 |  |
Total Long-term Balance | $ 47,301 | $ 14,713 | $ 117,043
2018 Average Rate | 3.60% |  |
2019 Average Rate | 1.60% |  |
2020 Average Rate | 3.22% |  |
2021 Average Rate | 3.44% |  |
2022 Average Rate | 4.50% |  |
Thereafter Average Rate | 1.96% |  |
Total Average Rate | 1.88% |  |

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- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
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