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Loans Held for Investment - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Receivables [Abstract] |  |  |  |  |
Loans renegotiated in troubled debt restructurings | $ 6,900,000 |  | $ 6,900,000 |  | $ 14,500,000
Troubled restructurings included in non-accrual loans | 4,800,000 |  | 4,800,000 |  | 11,300,000
Loans renegotiated in troubled debt restructurings, accrual loans | 2,100,000 |  | 2,100,000 |  | 3,200,000
Financing receivable, after allowance for credit loss, noncurrent | 100,000 |  | 100,000 |  | 2,900,000
TDR commitment to lend |  |  |  |  | $ 0
Troubled debt restructurings | 0 |  | 0 |  |
Charge-offs directly related to modifying troubled debt restructurings | 0 | $ 0 | 0 | $ 0 |
Balance of defaulted loans under trouble debt restructurings | 0 |  | 0 |  |
Impaired financing receivable, recorded investment | 148,500,000 |  | 148,500,000 |  |
Commitments to purchase or sell | 0 | 0 | 0 | 0 |
Proceeds from sale of loans held-for-investment | $ 0 | $ 0 | $ 0 | $ 0 |

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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 + Details
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- Definition Amount of financing receivable modified as troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554 + Details
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- Definition Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524 + Details
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- Definition Reflects the amount of the write-down related to a troubled debt restructuring. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554 + Details
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