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Servicing Assets - MSR Sensitivity Analysis (Details) - Mortgage Servicing Rights - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items] |  |
Fair value of residential mortgage servicing rights | $ 10,296 | $ 4,647
Weighted average life (years) | 9 years | 5 years
Prepayment speed | 7.26% | 9.39%
Impact on fair value of a 10% adverse change in prepayment speed | $ (358) | $ (183)
Impact on fair value of a 20% adverse change in prepayment speed | $ (695) | $ (354)
Discount rate | 9.00% | 9.00%
Impact on fair value of a 10% adverse change in the discount rate | $ (397) | $ (168)
Impact on fair value of a 20% adverse change in the discount rate | $ (768) | $ (329)

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- Definition Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719 + Details
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- Definition Estimated rate of prepayment of principal on financial assets for initial fair value measurement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719 + Details
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- Definition Weighted average life of securitized assets for initial fair value measurement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719 + Details
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- Definition The carrying amount (fair value) as of the balance sheet date of the transferor's interests in transferred financial assets (typically securitized receivables, generally not involved in the collection of principal) following transfer of significant portions of such financial instruments to other parties. Such interests could be ancillary cash flows and interest-only strips. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition The hypothetical financial impact of a 20 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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