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Variable Interest Entities (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Variable Interest Entities |  |  |
Unfunded contingent commitments | $ 27,831,000 |  |
Year in which commitments will be fulfilled | 2018 |  |
Impairment losses | $ 0 | $ 0 | $ 0
Other assets |  |  |
Variable Interest Entities |  |  |
Carrying value of equity investments in LIHTCs | $ 9,169,000 | $ 7,282,000 |
CDE |  |  |
Variable Interest Entities |  |  |
Tax credit period | 7 years |  |
LIHTC |  |  |
Variable Interest Entities |  |  |
Tax credit period | 10 years |  |
Tax credit compliance period | 15 years |  |

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- Definition The period in which a tax credit project must stay in compliance for the investor to keep the tax credits. + References No definition available. + Details
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- Definition Amount of write-down from impairment of an investment in a qualified affordable housing project. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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