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Qualified Affordable Housing Projects (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) commitment | Mar. 31, 2017 USD ($) | Dec. 31, 2017 USD ($) commitment
Other Commitments [Line Items] |  |  |
Qualified Affordable Housing Project Investments, Commitment |  |  | $ 0
Investment in qualified affordable housing projects | $ 8,000,000 |  | 8,700,000
Amortization expense included in noninterest expense | 700,000 | $ 800,000 |
Tax credits | 800,000 | $ 900,000 |
Federal Historic Tax Credit Project |  |  |
Other Commitments [Line Items] |  |  |
Investment in qualified affordable housing projects | $ 800,000 |  | $ 800,000
Number of open commitments to fund future investments | commitment | 1 |  | 1

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- Definition Amount of affordable housing tax credits and other tax benefits recognized. + 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 (a) -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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- Definition Amount of amortization expense 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 (c) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + 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 (e) -URI http://asc.fasb.org/extlink&oid=64813897&loc=SL49122993-202985 + Details
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