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Mortgage Servicing Rights - Schedule of Servicing Asset Key Economic Assumptions (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Servicing Asset Key Economic Assumptions [Line Items] |  |
Weighted average constant prepayment rate | 9.56% | 15.69%
Weighted average cost to service a loan | $ 90.57 | $ 87.58
Fixed Rate Conventional Loans |  |
Servicing Asset Key Economic Assumptions [Line Items] |  |
Discount rate | 9.30% | 8.51%
Loans Excluding Fixed Rate Conventional Loans |  |
Servicing Asset Key Economic Assumptions [Line Items] |  |
Discount rate | 10.61% | 9.51%

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- Definition [Line Items] for The key economic assumptions used to value servicing assets. + References No definition available. + Details
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- Definition Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Cost to Service Loans Per Loan + References No definition available. + Details
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- Definition Discount rate used to estimate the fair value of servicing assets and servicing liabilities. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122596-111746 + Details
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- Definition Estimated rate of prepayments of principal on servicing assets and servicing liabilities. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122596-111746 + Details
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