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Derivative Instruments and Hedge Activities - Summary of Amounts Included in Non-Interest Income in Consolidated Statements of Operations (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Derivative [Line Items] |  |  |  |
Amounts relating to derivative instruments, not designated in hedging relationship | $ 100 | $ 116 | $ 491 | $ (635)
Other Credit Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Amounts relating to derivative instruments, not designated in hedging relationship | 2 | 3 | 9 | (8)
Other Interest Rate Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Amounts relating to derivative instruments, not designated in hedging relationship | $ 98 | $ 113 | $ 482 | $ (627)

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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