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Qualified Affordable Housing Project Investments - Additional Information (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Schedule Of Equity Method Investments [Line Items] |  |  |
Investment for qualified affordable housing projects | $ 8,600,000 | $ 9,500,000 |
Unfunded commitments related to the investments in qualified affordable housing projects | 4,200,000 | 6,800,000 |
Amortization expense | 900,000 | 644,000 | $ 316,000
Recognized tax credits from its investment in affordable housing tax credits | 1,100,000 | 573,000 | 275,000
Impairment losses | $ 0 | $ 0 | $ 0
Minimum |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |
Expected year in which commitments are fulfilled | 2020 |  |
Maximum |  |  |
Schedule Of Equity Method Investments [Line Items] |  |  |
Expected year in which commitments are fulfilled | 2027 |  |

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- Definition Investment in affordable housing tax credits. + References No definition available. + Details
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- Definition Year in which contingent commitments to qualified affordable housing project investments are expected to be paid, in CCYY format. + References No definition available. + Details
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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Amount of amortization expense of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562 + Details
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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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