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Fair Value Measurement - Fair Value Assumptions (Details) - Fair Value, Inputs, Level 3 - Valuation Technique, Discounted Cash Flow | 3 Months Ended | 12 Months Ended
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Mar. 31, 2021 | Dec. 31, 2020
Minimum |  |
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items] |  |
Discount rate | 15.00% | 15.00%
Credit Risk Rate | 0.03% | 0.03%
Market-servicing rate | 0.75% | 0.75%
Prepayment rate | 8.61% | 9.07%
Maximum |  |
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items] |  |
Discount rate | 35.00% | 35.00%
Credit Risk Rate | 52.78% | 52.78%
Market-servicing rate | 0.75% | 0.75%
Prepayment rate | 88.79% | 89.01%
Weighted Average |  |
Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items] |  |
Discount rate | 22.88% | 22.69%
Credit Risk Rate | 17.73% | 17.19%
Market-servicing rate | 0.75% | 0.75%
Prepayment rate | 32.43% | 31.62%

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- Definition Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Market Servicing Rate + References No definition available. + 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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- Definition Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition Rate at which principal will not be repaid on securitized financial assets regardless of when the transfer occurred. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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